"But he's OK because he's going to get the job done, no matter what," Sanders told Fox News. "You can rest assured the President said he was going to build a wall, and he's going to deliver."

Citing two people who have spoken with the President, CNN reported that Trump has said he will sign the bill. The recent 35-day partial government shutdown was politically damaging for Trump and he appears inclined to avoid a repeat.

The Washington Post and CNN, citing White House officials, said Trump was likely to explore using his executive power to reallocate other federal funds for barrier projects along the southern border.

But the President has demonstrated that things could change quickly - his top spokeswoman said he and White House officials still want to see the final legislative text.

"They're still tinkering and making edits to that legislation and once we see what the final piece looks like, the President can make that decision," she said, referring to the House-Senate panel that crafted the border deal.

The Democratic-controlled US House of Representatives could vote as soon as Wednesday evening (local time), a senior aide said, despite not yet having produced a written copy of the agreement reached by congressional negotiators on Monday night.

The accord must also be passed by the Republican-controlled Senate and signed by Trump by the midnight Friday expiration of a stopgap measure that ended the longest federal shutdown in US history.

The measure's fate in the House was far from certain given the risk that conservatives and liberals will oppose the compromise for different reasons.

Congressional sources said the deal includes $US1.37 billion for new border fencing, about the same as last year - along 90 kilometres of the border - but not the $US5.7 billion Trump has demanded.

Senior congressional Republicans, showing little appetite for another shutdown after being heavily criticised for the previous one, urged Trump to support the agreement.

"I think the President will sign it. I think he will do so reluctantly, and then obviously, have to use executive actions to secure our borders," Republican Congressman Mark Meadows said.

"There are some positives in this bill, but it's certainly not enough," Sanders said in an interview with Fox News. "The President and his team have been looking at every option possible to get the full funding they need in order to complete the wall."

Trump surprised legislators when he withdrew support for a previous deal in December and demanded $US5.7 billion in wall funding, which was opposed by Democrats in Congress. That triggered a 35-day shutdown of about a fourth of the federal government that left 800,000 federal workers furloughed or working without pay.

The President previously threatened to declare a "national emergency" if Congress did not provide money specifically for the wall - a move that would almost certainly draw opposition in Congress and in the courts.

Sanders also offered a preview of the Trump team's messaging if he does sign the latest package by painting Democratic Speaker Nancy Pelosi as having given more ground than Trump.

"This has made some progress," she said. "Nancy Pelosi said she wasn't going to give a dollar for the wall. This has roughly $US1.4 billion that'll go towards the wall."

Trump made the wall a central 2016 campaign promise, calling it necessary to combat illegal immigration and drug trafficking. He said Mexico would pay for it, but Mexican officials rejected that.

Democrats have called a wall expensive, ineffective and immoral.

Reuters, Fairfax Media