Before the start of business, Just Security provides a curated summary of up-to-the-minute developments at home and abroad. Here’s today’s news.

IRAQ and SYRIA

Syria peace talks. The Syrian government delegation has said that the future of President Bashar al-Assad will not be a subject of discussion at peace negotiations, emphasizing the limited prospects of UN-brokered talks in Geneva. [Reuters]  Syria’s main opposition group, the High Negotiations Committee, postponed participation in the negotiations yesterday, withholding their engagement until the government delegation starts to discuss political transition for the country. [The Guardian’s Ian Black]  They have since said that the postponement is “indefinite” while “matters on the ground” remain unresolved. [Reuters’s Tom Perry and Laila Bassam]  Recent days have exposed infighting between the opposition. Sam Dagher reports. [Wall Street Journal]

Meanwhile, fighting has reportedly intensified in the north and center of Syria. [AP]

President Obama had an “intense conversation” with Russian President Vladimir Putin yesterday, Obama expressing concern over the fragility of Syria peace talks and heightened violence in Ukraine, the White House said. [New York Times’ Michael D. Shear and Nick Cumming-Bruce]

The AP is providing a timeline of latest updates on the UN-sponsored talks.

US military advisers are to be sent close to the front lines of the fight against ISIS in Iraq, Defense Secretary Ash Carter announced to American troops at the airport in Baghdad yesterday. The Pentagon will also deploy a number of Apache attack helicopters and long-range artillery to assist in the fight. [New York Times’ Michael S. Schmidt]  Carter also said that the “Iraqis are still in the lead” against ISIS, during an interview aired last night on “NBC Nightly News with Lester Holt.” [The Hill’s Rebecca Kheel]

“My expectation is that by the end of the year, we will have created the conditions whereby Mosul will eventually fall,” said President Obama speaking about the decision to increase support for the Iraqi military. [Reuters]

American and Kurdish forces killed Salman Abu Shabib al-Jebouri, known by the nom de guerre Abu Saif, according to the Kurdistan Regional Government Security Council yesterday. Jebouri was a member of the ISIS “military council.” [Wall Street Journal’s Matt Bradley and Paul Sonne]

China’s new special envoy to Syria is to visit Syria, Saudi Arabia, Iran and Russia in an effort to urge a peaceful solution to the Syrian war, according to the Chinese Foreign Ministry. Although China has largely left the matter to the other permanent members of the UN Security Council until now, this is a sign that it is attempting to become more involved, reports Ben Blanchard. [Reuters]

US-led airstrikes continue. The US and coalition military forces carried out three strikes against Islamic State targets in Syria on April 17. Separately, partner forces conducted a further 17 strikes against targets in Iraq. [Central Command]

“On the front line against ISIS: who fights, who doesn’t, and why,” an in-depth report from Scott Atran and Artis Research at The Daily Beast.

SAUDI ARABIA

President Obama will meet with the Gulf Cooperation Council in Riyadh, Saudi Arabia, this week. Issues likely to be on the agenda are Iran, the Syrian civil war, the conflict in Yemen, Islamic State and regional security. [New York Times]

There is a “public relations push” in Saudi Arabia ahead of President Obama’s visit tomorrow, reports Nahal Toosi, which has one goal: to demonstrate that Saudi Arabia is “as anti-terrorism as anyone in Washington DC” [Politico]

Saudi Arabia’s government paid “insufficient attention” to funds being sent to fuel the rise of al-Qaeda, President Obama’s deputy national security advisor Ben Rhodes said in an interview released yesterday. Asked about Saudi Arabia’s possible complicity in sponsoring terrorism, he said that it was a matter of “a number of very wealthy individuals” who contributed “sometimes directly” to terrorist groups. [Politico’s Eliza Collins]

The Justice Against Sponsors of Terrorism Act. The bill that would allow the Saudi government to be sued in a US court over any involvement in the 9/11 attacks has been approved by the Senate committee. The bill was supported by democratic presidential candidates Hillary Clinton and Bernie Sanders. [The Hill’s Julian Hattem]  However, the White House has indicated that President Obama will veto the legislation. [The Hill’s Jordan Fabian]

The White House is “confident” that Saudi Arabia will not go through with its reported threat to sell billions of dollars of US assets, spokesperson Josh Earnest said yesterday. [Reuters]

LIBYA

The UN-backed unity government moved last week to take political control of Libya following a “surprise” decision by the Tripoli administration to disband itself. [Wall Street Journal’s Tamer el-Ghobashy and Hassan Morajea]

UN-backed Prime Minister Fayez Seraj appealed for aid to fight Islamic State and rebuild a shattered Libya during his first video conference with EU foreign and defense ministers. The EU has responded by offering to assist with border management and with building police capacity. [The Guardian’s Patrick Wintour]

The EU is looking into “enhancing the capacity” of its naval mission in the Mediterranean Sea in anticipation of an “influx” of people heading for Europe from Libya and neighboring countries. [Financial Times’ Jim Brunsden]

The UK is keen to take a “leading role” in establishing stability in Libya, UK Foreign Secretary Philip Hammond offering support and £10 million-worth of aid to the unity government during his visit to Tripoli yesterday. It has also been suggested that the UK may supply ground troops to Libya as part of a 6,000-strong European force under Italian command, reports Jonathan Marcus. [BBC]

GUANTANAMO BAY

The transfer of nine detainees from Guantánamo Bay to Saudi Arabia over the weekend has been “blasted” by Republicans, who insist that it “unnecessarily” puts US citizens at increased risk. [The Hill’s Kristina Wong]

Released detainees’ writings “provide a glimpse” of how their “humanity endured in one of the bleakest prisons of the war on terror,” reports Murtaza Hussain. [The Intercept]

ISRAEL and PALESTINE

A bomb on a bus in Jerusalem wounded around 21 people yesterday, Prime Minister Benjamin Netanyahu describing the explosion as a “terrorist attack,” though no perpetrators have been identified as yet. [New York Times’ Isabel Kershner]

Yosef Haim Ben David has been convicted of the 2014 murder of a Palestinian teenager in revenge for the abduction of three Israeli youths, an incendiary event which helped to instigate the subsequent war in Gaza. Ben David’s two accomplices have already been convicted and sentenced. [AP; Reuters’ Jeffrey Heller]

The US feels “overwhelming frustration” at Israel’s government and its expansion of Jewish settlements. Vice President Joe Biden was speaking to the J Street lobby group in Washington yesterday about the US’s relationship with the Israeli government, stating that the US also has an “overwhelming obligation” to press for the “only ultimate solution” to the Israel-Palestine conflict, a two-state solution. [Reuters’ Lesley Wroughton]

EUROPEAN TERROR THREAT

There are “indications” that Islamic State has sent more fighters to Europe, according to Belgian authorities. [Reuters’ Robert-Jan Bartunek]

German authorities have arrested five people on suspicion of forming a right-wing terror group, designed to attack the homes of refugees and other facilities, prosecutors said. [AP]

A Moroccan man with suspected links to ISIS has been arrested by authorities in the Mediterranean island of Mallorca. [AP]

“Suddenly – and belatedly – leaders are willing to admit that extreme interpretations of Islam are a problem.” John Vicocur discusses what he describes as a “clash of civilizations” underway in Europe. [Wall Street Journal]

CYBERSECURITY, PRIVACY and TECHNOLOGY

There should be limits on the government’s powers to conduct covert email searches, said Bill Gates yesterday, expressing his support for Microsoft Corp’s lawsuit against the government seeking freedom to inform customers when their data has been sought by federal agencies. [Reuters]

China has suggested that the US military may hack itself in order to increase budgets and present Beijing in a negative light. [The Hill’s Cory Bennett]

OTHER DEVELOPMENTS

The Russian fighter jet “barrel-rolled” over the US spy plane it flew close to last Thursday, the Pentagon has claimed. This was the second of two similar incidents in the Baltic Sea the past week, the first involving a Russian aircraft performing a “simulated attack profile” on a US warship, though neither of the Russian planes involved appeared to be armed, the Pentagon has confirmed. [AFP]  NATO is due to discuss Russia’s actions when ambassadors meet with Russian officials tomorrow, secretary-general Jens Stoltenberg has said. [Wall Street Journal’s Julian E Barnes]

A suicide bombing and gun attack hit a government security agency in Kabul, Afghanistan, this morning, killing “dozens” and injuring hundreds of people. The Taliban has claimed responsibility, saying that it detonated a truck filled with explosives. [Wall Street Journal’s Jessica Donati and Ehsanullah Amiri; AP]

A suicide attack in the northwestern city of Mardan, Pakistan, has killed at least one person today. A spokesperson for the militant group Jamat-ul-Ahrar claimed responsibility for the attack. [AP’s Riaz Khan]

UK ministers have discarded a plan to introduce a war powers act that would cement into law a convention that parliamentary approval is required before troops are sent into combat, except in an emergency. Defense Secretary Michael Fallon told MPs that he and the prime minister did not want to be “artificially constrained in action to keep this country safe.” [The Guardian’s Richard Norton-Taylor]

China has declined to respond to queries from the US military in relation to its use of a military aircraft to evacuate sick workers from one of its man-made islands in the South China Sea on Sunday. [Reuters’ Ben Blanchard]