WASHINGTON — Congressional negotiators reached an agreement Monday night to prevent a government shutdown and finance construction of new barriers along the US-Mexico border, overcoming a late-stage hang-up over immigration enforcement issues that had threatened to scuttle the talks.

Our staff is just working out the details

Republicans were desperate to avoid another bruising shutdown. They tentatively agreed to far less money for President Donald Trump’s border wall than the White House’s $5.7 billion wish list, settling for a figure of nearly $1.4 billion, according to congressional aides. The funding measure is through the fiscal year, which ends 30 September.

The agreement means 55 miles of new fencing — constructed through existing designs such as metal slats instead of a concrete wall — but far less than the 215 miles the White House demanded in December. The fencing would be built in the Rio Grande Valley in Texas.

“With the government being shut down, the specter of another shutdown this close, what brought us back together I thought tonight was we didn’t want that to happen” again, said Senate Appropriations Committee Chairman Richard Shelby, R-Ala.

Details won’t be officially released until Tuesday, but the pact came in time to alleviate any threat of a second partial government shutdown this weekend. Aides revealed the details under condition of anonymity because the agreement is tentative.

“Our staff is just working out the details,” said House Appropriations Committee chairman Nita Lowey, D-N.Y.

The pact also includes increases for new technologies such as advanced screening at border entry point, humanitarian aid sought by Democrats and additional Customs officers.