As the federal funding deadline passed, the White House has begun orderly shutdown preparations amid a political impasse in Congress that has left part of the government without appropriations.

Despite intense last-minute negotiations between the executive branch and Senate Democrats, the House of Representatives remains out of session until Monday, making it unlikely that a funding package can be enacted before the partial lapse of appropriations just after midnight on Friday.

President Donald Trump and congressional leaders, including Senate Majority Leader Chuck Schumer, struck a compromise in the Senate to keep most federal agencies funded through September and to extend funding for the Department of Homeland Security (DHS) for two additional weeks, allowing further debate on proposed reforms to immigration enforcement.

The Senate approved the measure by a substantial margin, signalling broad support for averting a prolonged shutdown.

However, because the House is not expected to take up the legislation until it reconvenes, a partial government shutdown affecting departments such as the Internal Revenue Service, the Federal Emergency Management Agency and the Transportation Security Administration will begin over the weekend.

Essential services including Social Security, postal operations, national parks and museums are likely to remain operational, while many federal workers may be furloughed or work without immediate pay until the funding measure is approved.

The impasse largely reflects disagreements over proposed policy changes for Homeland Security and immigration agencies, which Senate Democrats have tied to their support for continued funding.

Trump has urged both parties to approve the Senate deal and emphasised the importance of bipartisan cooperation to keep government services running.

Republican leaders, including House Speaker Mike Johnson, have expressed opposition to segmenting spending bills but stressed their intent to pass the measures swiftly upon return.

Administration officials and lawmakers on both sides have framed the expected shutdown as likely to be short-lived, with efforts underway to complete the legislative process early next week.

The White House has instructed federal agencies to activate contingency plans for minimal disruption and to ensure continuity of critical functions.

As Congress races to finalise the stopgap funding, both the executive branch and lawmakers have signalled that a prolonged closure is not in the national interest, and focus remains on reaching a final agreement that funds the government through the remainder of the fiscal year with minimal interruption.