By Jeff Mason

WEST PALM BEACH, Fla. (Reuters) – U.S. President Donald Trump on Thursday was due to fly back to Washington a day earlier than planned, as he continued his fight with Congress over a defense bill and stimulus checks as well as a long-shot bid to overturn his November election defeat.

Trump, who originally was scheduled to attend a New Year’s Eve party at his Mar-a-Lago resort in Florida, is expected to leave for Washington at around 11 a.m. EST (1600 GMT).

The White House has given no reason for the change, but it coincides with Trump’s fight with Congress over his veto of a major defense bill and his demand for increased COVID-19 stimulus checks, as well as a spike in tensions with Iran.

Senate Majority Leader Mitch McConnell, the top Republican in the chamber, dealt a likely death blow on Wednesday to Trump’s bid to boost coronavirus aid to Americans, declining to schedule a swift vote on a bill to raise relief checks to $2,000 from the $600 included in the relief package passed by Congress earlier this month.

Trump had ramped up pressure on fellow Republicans to back the bigger checks for struggling Americans in a series of tweets in recent days in which he attacked Republican leaders as “pathetic” and accused the party of having a “death wish” if it did not increase stimulus payments.

Republicans in Congress have largely stuck with Trump through four turbulent years, but the president is angry that they have not fully backed his claims of election fraud in the Nov. 3 election that was won by Democrat Joe Biden.

The tensions among Republicans have been exacerbated by a second showdown over an effort in Congress to override Trump’s veto of a defense policy bill.

The Republican-controlled Senate voted 80-12 on Wednesday to begin debate on the issue, with another procedural vote due on Friday. If successful, the effort would lead to the first veto override of Trump’s presidency.

The Democratic-controlled U.S. House of Representatives voted to overturn Trump’s defense bill veto on Monday.

U.S.-Iran tensions, meanwhile, have again spiked.

Iranian Foreign Minister Mohammad Javad Zarif on Thursday accused Washington of trying to fabricate a pretext for attacking his country and vowed Tehran would defend itself even though it does not seek war.

Two U.S. B-52 bombers flew over the Middle East on Wednesday in what U.S. officials said was a message of deterrence to Iran ahead of the first anniversary of a U.S. drone strike that killed top Iranian general Qassem Soleimani.(This story has been refiled to fix typographical error in headline)

(Reporting by Jeff Mason and David Brunnstrom; Editing by Noeleen Walder and Paul Simao)