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There was no breakthrough in talk to reopen the Department of Homeland Security (DHS) on Wednesday as the shutdown extends to almost six weeks with no end in sight.

Democratic lawmakers demanded new restrictions on federal agents carrying out the president’s deportation crackdown. But Republicans rejected the proposal, offering instead to remove money for immigration enforcement from the homeland security spending bill.

The Senate minority leader, Chuck Schumer, quickly shot down the offer, and said Democrats had countered with a measure that coupled DHS funding with a host of new guardrails on immigration enforcement operations – something the party has insisted on for months.

But that gained no traction with the GOP. “Get serious, folks,” the Senate majority leader, John Thune, said, in response to the Democrats’ counteroffer.

The funding lapse has led to lengthy lines at Transportation Security Administration (TSA) checkpoints at some major airports, including including Hartsfield-Jackson Atlanta international airport and George Bush intercontinental airport in Houston, prompting the president to this week deploy ICE agents in a bid to relieve congestion.

White House press secretary Karoline Leavitt confirmed yesterday that nearly 500 TSA officers have quit since what she called “the Democrat shutdown” began.

“This is a dire situation,” the acting TSA administrator Ha Nguyen McNeill testified at a House hearing Wednesday.

The standoff seems likely to prolong the partial government shutdown, which began in mid-February after Democrats refused to approve funding for the department overseeing Immigration and Customs Enforcement (ICE), border patrol and other agencies involved in Donald Trump’s mass deportation push, without reforms demanded in response to the deaths of two US citizens in Minneapolis at the hands of federal agents.

Meanwhile, Schumer has sought to place the blame on Republicans for the travel chaos, saying its most recent proposal disrupted talks that had been nearing a compromise.

“We thought there had been some progress. Then Republicans sent us their offer yesterday, and it contained none of what we talked about, none of the reforms we had been discussing,” Schumer said on the Senate floor. “So if anyone is slowing down negotiation and hurting TSA workers, it is the Republican leadership, who did not include one single reform.”

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In other developments:

• The acting head of the Transportation Security Administration (TSA) said on Wednesday that airports across the country are experiencing the “highest wait times in TSA history”, as the partial shutdown of the DHS enters its sixth week. At a House homeland security committee hearing, Ha Nguyen McNeill said her agency has been shut down for 50% of the fiscal year so far – a stretch that includes last year’s record-breaking 43‑day lapse in federal funding. She told lawmakers that by Friday, TSA employees will have missed $1bn in paychecks as a result of the closures. More here.

• The US has launched another strike on a vessel in the Caribbean, killing four people, the US Southern Command said. The command, which oversees combatant operations in Latin America and the Caribbean, announced on X that it had conducted a “lethal kinetic strike on a vessel operated by Designated Terrorist Organizations”. More here.

• Progressive lawmakers have unveiled a new policy to place a moratorium on the construction of AI datacenters. The policy, announced by Bernie Sanders, an independent senator from Vermont, and Alexandria Ocasio-Cortez, a New York Democratic representative, aims to ensure the AI boom protects the environment and communities, and benefits workers instead of harming them. More here.

• The Trump administration’s federal housing director Bill Pulte is asking prosecutors to investigate New York attorney general Letitia James for insurance fraud, according to criminal referrals reported by MS Now and CBS News. The referrals to prosecutors in Florida and Illinois allege that James may have committed mortgage insurance fraud. The allegations center on applications made to Universal Property Insurance company, which is based in Florida, and Allstate in Illinois. More here.