A US pastor known for his staunch support of Donald Trump has called on Christians to pray for Joe Biden following the Democrat's victory in this year's presidential election.

In a column at Fox News, Trump devotee Rev Robert Jeffress seemed to have largely accepted the result at the polls, while the Trump campaign refuses to concede the loss and fights to prove allegations of widespread voter fraud.

"It appears that former Vice President Joe Biden will become the 46th president of the United States on Jan. 20," Jeffress wrote, "unless President Trump succeeds in legal challenges to the counting of votes in several states".

Jeffress, the senior pastor of Frist Baptist Church in Dallas, went on to write that "when Joe Biden becomes president, we should commend him for the things he does right" and "condemn the things he does wrong".

"And above all," the Texan minister urged, "we must pray fervently for our president." 

The pastor admitted it was "always easier to submit and to pray for someone when he was our preferred candidate. But the rubber really meets the road when the person who takes office is not the one we supported".

“Here is our chance to show that Christians are not hypocrites," he urged. 

An outspoken and loyal supporter of the president, Jeffress later took to Twitter to clarify reports that he had broken rank with Trump.

"Don’t believe some false media reports that I have “broken” with our great President Donald Trump," he wrote. "I support him completely. We do NOT have a “president-elect” until electoral college votes December 14." 

The baptist pastor also noted that the headline for his Fox News piece — 'Pastor Robert Jeffress: Biden is president-elect — how should Christians respond?' — was not written by him. "Fox chose that title, not me," he said. 

Others — even some of those from Trump's own party — have been less guarded about admitting Biden's victory. On Thursday, the Republican governor of Ohio, Mike DeWine, told CNN: "Joe Biden is the president-elect." 

On Wednesday, the Trump campaign announced it would be submitting 234 pages of sworn affidavits to a federal court in Michigan.

His campaign adviser and press secretary, Kayla McEnany, brandished the bundle of documents on Fox News, insisting that it contains a litany of evidence proving fraud at the polls.