Hello and welcome to the US politics live blog.

Airports continue to warn passengers to arrive several hours early due to unpredictable Transportation Security Administration (TSA) wait times, as the shutdown of the Department of Homeland Security (DHS) became the longest shutdown in US history.

Congress and Donald Trump have made various attempts to direct government money toward the DHS, or directly to the DHS-funded TSA, but each have ended without success as an impasse over changes to Immigration and Customs Enforcement (ICE) operations remains deadlocked.

With 9.4% of the total federal workforce, numbering 193,867 employees, the DHS is the fourth-largest agency in the US government. The agency said that more than 480 TSA workers have left altogether since the start of the shutdown.

White House border czar Tom Homan said it depends on how many TSA employees would be returning to work after they start receiving their pay.

“ICE is there to help our brothers and sisters in TSA. We’ll be there as long as they need us, until they get back to normal operations and feel like those airports are secure,” he told CBS’ ‘Face the Nation’.

Speaking on CNN’s ‘State of the Union’, Homan said it also depends on how many TSA agents “have actually quit and have no plan on coming back to work.” Nearly 500 TSA officers have left the agency since the shutdown started, according to DHS.

He added that he hopeed TSA officers will be paid today or by Tuesday . “It’s good news because these TSA officers are struggling,” Homan said. “They can’t feed their families or pay their rent.”

Trump signed a memo late on Friday ordering DHS to restore pay to TSA employees, who have missed two paychecks, but it is unclear where that money will come from and if he can legally direct the agency to pay the employees.

The presidential memorandum directed the DHS secretary, Markwayne Mullin, to send funds “that have a reasonable and logical nexus to TSA operations” to pay TSA employees with the pay and benefits “that would have accrued” if no shutdown had happened.

Read the full story here:

In other developments:

• A generational divide over the Iran war has emerged between older attendees and their political heirs at this year’s Conservative Political Action Conference (CPAC) in Texas, as the group’s leaders pleaded for unity ahead of a challenging midterm election year for Republicans. More here.

• Iran has warned the US that it is prepared to confront any ground assault, accusing Washington of secretly planning a land attack while publicly seeking talks, as the war that has killed thousands of people and caused the biggest ever disruption to global energy supplies entered its second month. More here.

• US lawmakers have responded to reports that the Pentagon is preparing for weeks of ground operations in Iran as thousands of US troops assemble in the Middle East and the conflict showed signs of entering a more dangerous phase. More here.

• The abortion rate is holding steady in the US despite total and partial bans in some states – largely because of travel across state lines and a significant increase in telehealth appointments, a new report says. More here.

• Pope Leo has said God ignores the prayers of leaders who wage war and have “hands full of blood”, in an apparent rebuke to the Trump administration. The pontiff made the comments on Sunday as thousands of US troops arrived in the Middle East.

• More than 8 million people protested against the Trump administration at more than 3,300 No Kings events across the US and in more than a dozen countries on Saturday, according to organizers.