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.

IRAN-SAUDI ARABIA DISPUTE

Iran has accused Saudi Arabia of conducting air attacks on the Iranian Embassy in Sana’a, Yemen, the latest development in the complex ongoing dispute between the two nations. [The Guardian]

Iran’s President Hassan Rouhani has called on the country’s courts to prosecute protesters who attacked the Saudi Embassy over the weekend. [Washington Post’s Carol Morello and Erin Cunningham]

Iranian diplomats have left Saudi Arabia, reports the AP, returning to Tehran following Riyadh’s decision to cut diplomatic ties.

Beijing has dispatched an envoy to Riyadh and Tehran in an effort to quell tensions between the two nations, urging both to exercise restraint. [Reuters]

Iraq sent its foreign minister to Iran yesterday, offering to mediate between Tehran and Riyadh; the move highlights Baghdad’s fears that fresh sectarian tensions in the region could have an adverse impact on its efforts to tackle ISIS. [Reuters]

More countries have sided with Saudi Arabia in the dispute with Iran, Qatar becoming the latest country to pull diplomatic ties with Tehran. [Al Jazeera]

Saudis have welcomed the tough line adopted by the kingdom, with many viewing the executions as an act of “simple justice,” reports Robert F. Worth. [New York Times]

“One map that explains the dangerous Saudi-Iranian conflict,” from Jon Schwarz at The Intercept.

NORTH KOREA NUCLEAR TEST

The UN has threatened to impose new punitive measures against North Korea following its claim to have tested a hydrogen bomb. It is as yet unclear whether the international community would agree on an approach for containing the country’s nuclear program. [The Guardian’s Julian Borger]  The Security Council strongly condemned the test while Secretary General Ban Ki-moon described it as “a grave contravention of the international norm against nuclear testing.” [UN News Centre]

President Obama’s administration has reacted to reports of the nuclear test with the “same mix of condemnation, exacerbation and pleas for collective action” as have been seen before, as Republicans call for a stronger response. [The Guardian’s Spencer Ackerman and David Smith]  White House officials have cast doubt on Pyongyang’s claims to have tested a hydrogen bomb, saying that initial data is “not consistent” with an explosion of that kind. [New York Times’ Somini Sengupta et al]

The Obama administration has focused on Iran’s nuclear capabilities while pursuing a “decidedly less clear strategy” on North Korea, reports David Nakamura. [Washington Post]

The news of the nuclear test poses fresh challenges to US policy in Asia, reinforcing the need for Washington to counter China’s influence in the region. Carol E. Lee reports. [Wall Street Journal]

The incident brings once again to the fore the question of how to contain North Korea, given the country’s “way of acting out when they feel ignored.” [New York Times’ David E. Sanger]

Pyongyang’s nuclear test claim puts pressure on ties with Beijing, its neighbor and chief ally. Javier C. Hernández reports for the New York Times.

South Korea will restart cross-border propaganda broadcasts in response to North Korea’s announced nuclear test; the broadcasts are considered acts of war by Pyongyang. [AP]  Seoul is also in talks with Washington over the deployment of US strategic weapons to the Korean peninsula, according to a South Korean military official. [Reuters]

Pyongyang’s claim of a nuclear test is as important to the country’s dictatorship at home as it is abroad, helping to “cement loyalty” to leader Kim Jong Un. [Wall Street Journal]

The Wall Street Journal editorial board comments on the “new nuclear proliferation age,” suggesting the “larger story” in the wake of North Korea’s claimed test is the “rapid fraying of the world’s antinuclear proliferation regime.”

IRAQ and SYRIA

Speaker Paul Ryan is calling on GOP committee chairmen to look into whether there is House support to formally authorize the military campaign against ISIS in Syria and Iraq, although there remains skepticism that he will rally sufficient support for a new AUMF, report Jake Sherman and John Bresnahan. [Politico]

The great challenges posed in rebuilding Ramadi following its capture by Iraqi forces from ISIS “bear testament to the tremendous costs of dislodging a group that stitches itself into the fabric of communities.” [New York Times’ Ben Hubbard]

Residents of Madaya, a besieged Syrian town close to Damascus say they are being starved to death as a result of the months-long siege by forces loyal to the Assad regime. [The Guardian’s Kareem Shaheen and Emma Graham-Harrison]

US-led airstrikes continue. US and partner military forces carried out one airstrike against Islamic State targets on Jan. 5. Separately, coalition forces conducted a further 19 strikes on targets in Iraq. [Central Command]

“Inside IS terror weapons lab,” from Stuart Ramsay at Sky News.

“The overall result has been a complex mix where any kind of policy – cultural or otherwise – might require subtlety.” Gareth Smyth discusses Iran’s “failed” cultural diplomacy in Syria, at the Guardian.

OTHER DEVELOPMENTS

A bomb attack targeting a police training center in western Libya has killed at least 40 people, according to the town’s mayor and hospital sources. There was no immediate claim of responsibility. [The Guardian]  And five oil storage tanks are ablaze following ISIS attacks on Libya’s biggest oil ports, Es Sider and Ras Lanuf. Fighting reportedly continues. [Reuters]

Two Guantánamo Bay detainees of Yemeni origin have been resettled to Ghana, the Pentagon announced. It is the first time that lower-level prisoners have been sent to sub-Saharan Africa and the transfers are expected to be the start of a “flurry” of 17 resettlements early this year. [New York Times’ Charlie Savage]

The heaviest airstrikes yet reported in the nine-month Yemeni civil war took place today, with dozens of strikes hitting Sana’a. [Reuters]

The House Intelligence Committee will explore the need for new safeguards to handle communications intercepted by the NSA involving American lawmakers or citizens, the committee’s chairman, Rep Devin Nunes said. [Wall Street Journal’s Adam Entous]

Former CIA Director David Petraeus appeared before the House Benghazi committee yesterday for a four-hour hearing. [The Hill’s Julian Hattem]  And Democrats on the committee have criticized the Republican-led investigation for taking longer than the 9/11 probe. [Politico’s Rachael Bade]

Military drone pilots will now be eligible for military honors comparable to those awarded to pilots who fought in Iraq and Afghanistan, the Defense Department will today announce. [New York Times’ Michael S. Schmidt]

President Obama is set to nominate Gen Joseph L. Votel, the current leader of Special Operations Command, to replace Gen Lloyd J. Austin as the new head of US Central Command, Pentagon officials said yesterday. [New York Times’ Helene Cooper]

Guatemalan prosecutors announced the arrest of 18 former military officials on charges connected to massacres and disappearances during the country’s civil war. [New York Times’ Elisabeth Malkin]

“There’s a reason the US and NATO countries are the targets of this type of violence but South Korea, Brazil and Mexico are not.” Glenn Greenwald explores the “deceptive debate” over the causes of terrorism against western states. [The Intercept]