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

Battle for Tikrit continues. Fierce clashes between Iraqi forces and ISIS militants continued on the outskirts of Tikrit on Sunday. [Al Jazeera] Iraqi troops and pro-government militias have made advances in two key areas surrounding Tikrit, a week after launching the counteroffensive to reclaim the strategic Iraqi city. [Washington Post’s Erin Cunningham]

Iraqi troops have reclaimed the western town of al-Baghdadi with the help of “precise and effective” airstrikes by the U.S.-led coalition. [U.S. Central Command]

A U.S.-led coalition airstrike hit an ISIS-held oil refinery in Syria yesterday, killing 30 people, according to the Syrian Observatory for Human Rights. [Reuters]

Syrian Kurds resisted a new assault by ISIS on Christian villages in northeastern Syria over the weekend, as Hasakah province emerges as the new scene of battle in the fight against the Islamic State. [Wall Street Journal’s Sam Dagher]

A Canadian soldier was killed in a friendly fire incident in Iraq on Friday. Canadian and Kurdish accounts of the death differed; Kurdish officials said he had shown up with a group of soldiers unannounced and was directing airstrikes on the front lines, but Canadian officials contradicted this report. [AP’s Bram Janssen and Rob Gillies]

The U.S. is bearing the “bulk of the military burden” in the fight against ISIS; 2,203 of 2,738 coalition airstrikes in Iraq and Syria since last summer have been carried out by American forces. [Washington Post’s Miss Ryan]

Nigeria-based Boko Haram has pledged allegiance to the Islamic State, according to an audio message released on Saturday reportedly from the group’s leader, Abubakar Shekau. [CNN’s Nima Elbagir et al] Nancy A. Youssef and Philip Obaji Jr. question whether this is a genuine alliance or a mere “marriage of convenience.” [The Daily Beast] And Al Jazeera explores the reasons for the pledge and the consequences for Nigeria.

The Islamic State ­appears to be beginning to “fray from within,” with growing friction between foreign and local recruits and signs of disillusionment among some fighters, reports Liz Sly. [Washington Post]

Iraqi cultural officials are calling for more military assistance from the international coalition against ISIS to counter the group’s destruction of ancient artifacts and monuments. [Wall Street Journal’s Tamer El-Ghobashy and Ghassan Adnan]

The FBI is investigating the hacking of several U.S. and European websites by individuals claiming to be linked to ISIS over the weekend, although law enforcement and security analysts do not suspect ties to the Islamic State. [NBC News’ M. Alex Johnson]

Two Australian teenagers were stopped at Sydney airport on suspicion of attempting to travel to Syria to join the Islamic State. [ABC’s Andrew Greene]

IRAN NUCLEAR DEAL

Secretary of State John Kerry stressed unity with French Foreign Minister Laurent Fabius over the weekend on the nuclear negotiations with Iran. Kerry said that a “critical couple of weeks” lie ahead as the countries try to close the remaining gaps. [Wall Street Journal’s Felicia Schwartz]

President Obama said Iran has been offered an “extraordinarily reasonable deal,” but vowed to “absolutely” walk away if a deal could not be reached that would prevent Tehran from obtaining a nuclear weapon. [CBS’ “Face the Nation”]

The president “cannot work around Congress forever,” Senate Majority Leader Mitch McConnell said yesterday, noting that Obama will need Congress to lift any existing Iran sanctions. [CBS’ “Face the Nation”] Meanwhile, Sen. Dianne Feinstein said a nuclear agreement is required “to protect from a breakout,” while calling the Israeli leader’s address last week “humiliating” and “arrogant.” [NBC’s “Meet the Press.”]

A deal with Iran is a “matter of survival” for Israel, Prime Minister Benjamin Netanyahu said on CBS’ “Face the Nation.” Netanyahu also acknowledged the critical National Security Council tweet from last week, suggesting that it is “useful to remember who your ally is.”

Congress “could still sabotage” a deal through the latest Iran bill, warns the New York Times editorial board, suggesting an alternative way in which Congress could play a role moving forward. And former White House official Gary Sick explores the dangers of unsuccessful Iran talks. [Politico Magazine]

RUSSIA and UKRAINE

The Ukrainian military has accused pro-Russian rebels of violating a ceasefire agreement, reporting 16 attacks on government positions overnight [RFE/RL]

Europe is not yet ready to impose further sanctions on Russia, European Council President Donald Tusk has said ahead of his scheduled meeting with President Obama in Washington today. [New York Times’ James Kanter and Andrew Higgins]

Two Chechen men have been charged in connection with the murder of Russian opposition leader Boris Nemtsov; three further suspects are in custody and a sixth suspect is reported to have killed himself in an encounter with police. [BBC]

NIGERIA

Multiple bombings in Maiduguri, in Nigeria’s northeast, killed at least 50 people on Saturday; there was no immediate claim of responsibility for the attacks that appeared to be carried out by Boko Haram. [Al Jazeera America]

Chad and Niger have launched a joint “ground and air” offensive against Boko Haram militants in Nigeria, a day after the group pledged allegiance to the Islamic State. [Al Jazeera]

YEMEN

Yemen’s defense minister has escaped the capital, controlled by Houthi rebels, and joined President Abed Rabbo Mansour Hadi in Aden, according to security officials. [AP]

Arab League foreign ministers are meeting in Cairo today to discuss coordinated action on Yemen, but there may be “no simple solutions,” reports Deutsche Welle.

OTHER DEVELOPMENTS

A report of the UN special rapporteur on torture investigating allegations of torture and abuse in 68 countries will be delivered to the Human Rights Council today. [The Guardian’s Ben Doherty and Daniel Hurst]

Hillary Clinton came under fire for her use of private email on the Sunday political shows; The Hill provides a useful wrap-up. The email revelations are testing the relations between the former secretary of state’s emerging campaign and the White House, report Carol E. Lee and Colleen McCain Nelson. [Wall Street Journal]

The military has been given permission to fast-track the hiring of 3,000 computer expert civilians, in an effort to boost the department’s cyber defenses. [Nextgov’s Aliya Sternstein]

Libya’s internationally recognized government carried out strikes earlier today against the last functioning airport in Tripoli, which is being controlled by rival factions. [Reuters] The latest attacks on Libya’s oil fields, believed to be carried out by Islamic State militants, appear to be aimed at halting oil production rather than taking control over it. [Wall Street Journal’s Benoît Faucon and Matt Bradley]

Israeli Prime Minister Benjamin Netanyahu has denied reports that he had withdrawn support for a two-state solution, after a statement from Netanyahu’s party suggested such a move. [Al Jazeera]

An attack in northeastern Mali over the weekend killed two children and a UN peacekeeper from Chad. [UN News Centre]

Afghanistan’s peace efforts involving Pakistan are being treated skeptically by many Afghans, who distrust the Pakistan military for its role in the Taliban’s early years, report Mujib Mashal and Azam Ahmed. [New York Times]

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