With the clock ticking before the US enters the second government shutdown in as many months, tension was rising on Wednesday over whether Donald Trump would sign the latest deal over a modest border barrier – amid signs the agreement might be facing a last-minute implosion.

Trump not 'thrilled' with border deal reached by lawmakers Read more

As all eyes turn to the midnight deadline on Friday – when, if there is no final accommodation, parts of the federal government will close – reports suggested Trump was grudgingly minded to sign off the deal reached by congressional negotiators. It would give him less than $1.4bn for his border wall with Mexico – substantially less than he has demanded – though his senior aides have hinted heavily that he would try to take additional funds from other federal budgets.

CNN on Wednesday morning reported that they had talked to two anonymous sources who said Trump intended to sign the deal to prevent a repeat of last month’s shutdown, the longest such disruption in US history. That echoed CBS News, which said an unnamed official had told them Trump would be “very likely” to sign should the agreement land on his desk.

But further jitters erupted after it was reported that the deal may yet be facing difficulties even before it reaches the Oval Office. The compromise formula agreed by a panel of 17 negotiators from both parties might now be “unraveling a bit”, according to Politico.

“It seems as if the deal was announced a bit too early,” Politico said, adding quizzically that there were “both critical issues and ancillary issues that were not yet solved”.

Politico’s list of sticking points as lawmakers seek to draft the agreement into actual legislation does not look overly serious, and includes points of language over the border settlement.

In El Paso at his first rally of 2019 on Monday night, Trump’s new theme, if the banners around the venue were anything to go by, appeared to be “finish the wall” not “build the wall”, as was the chant he led previously.

Regardless, not a mile of new wall has been built on the US-Mexico border since Trump took office promising to create such a “beautiful” thing along the 1,900-plus miles of border. Some existing barrier sections have been replaced or refurbished, mainly with slatted fencing, amid a lack of agreement to fund the president’s long-promised project.

Talks are also reportedly stuck over whether or not to insert back-pay for federal contractors hit by the last government shutdown.

Play Video 0:43 Trump: 'Just so you know, we're building the wall anyway.' – video

But as Politico points out: “Many of these issues can be worked out, but there is very little time.” If the Friday deadline is to be met, the House of Representatives needs to vote on the final bill on Wednesday so that it can be sent to the Senate on Thursday and to Trump in good time.

As America entered the final 76 hours before the deadline, Trump continued to keep everyone guessing. “I can’t say I’m happy. I can’t say I’m thrilled,” he said of the draft agreement that emerged from Congress on Tuesday.

But he told a cabinet meeting that when it came to another shutdown: “I don’t think it’s going to happen.”

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While grumbling about the terms of the deal, which would give him only 55 miles (88km) of new border fencing in the Rio Grande Valley in Texas as opposed to the 215 miles (345km) he had demanded in December, Trump has also made increasingly threatening noises about raiding federal budgets to supplement the sum granted by Congress. ABC News reported that the White House, which has been studying this matter for months, is looking closely at the possibility of swiping funds from the Department of Defense under an obscure rule allowing resources to be diverted to counter illegal drugs.

ABC News also said the Pentagon was reviewing whether the military construction budget could be reallocated to the border wall.

Acting White House chief of staff Mick Mulvaney said last week: “We’ll take as much money as you can give us, and then we will go off and find the money someplace else legally in order to secure that southern barrier.”

The nuclear option would be for Trump to declare a national emergency, which would give him access to a much greater pot of federal money while effectively bypassing the will of Congress. That would send a constitutional jolt through Washington that even senior Republicans are reluctant to see implemented by a Republican president.