WASHINGTON • US President Donald Trump has appeared to backtrack on accepting campaign help from Russia or other foreign governments without necessarily telling the FBI, saying he would inform law enforcement if he were approached.

Under fire for saying earlier in the week that "I'd take it" and scoffing at the notion that he should call the authorities, Mr Trump on Friday shifted his stance by saying that while he would still look at incriminating information provided by a hostile foreign power about an election opponent, he would "absolutely" report such an encounter.

"Of course, you give it to the FBI or report it to the attorney-general or somebody like that," Mr Trump said on Fox & Friends. "But of course you do that. You couldn't have that happen with our country."

He shot back angrily, however, at House Speaker Nancy Pelosi, who had said on Thursday that the President's willingness to take foreign help to win an election demonstrated "that he does not know right from wrong" and that "he's been involved in a criminal cover-up".

Calling it a "fascist statement", Mr Trump said: "When Nancy Pelosi makes a statement like that, she ought to be ashamed of herself. It's a disgrace."

Mr Trump's comments on taking campaign help from Russia came after more than a day of withering criticism from Democrats, and even uncomfortable distancing from Republicans who said any candidate should automatically report a foreign effort to influence US elections.

With his initial remarks earlier in the week, Mr Trump had put his relationship with Moscow back into the centre of the debate in Washington over the future of the presidency after special counsel Robert Mueller reported that he could not establish any criminal conspiracy between the Trump campaign and Russia during the 2016 election.

He reopened the issue during an interview with ABC News, when he dismissed the notion that a candidate should call the Federal Bureau of Investigation if approached by a foreign power with election help. "I don't think in my whole life I've ever called the FBI. In my whole life," he said. "You don't call the FBI. You throw somebody out of your office, you do whatever you do."

Those comments stirred a fresh furore on Capitol Hill, fuelling calls for legislation requiring US political campaigns to report foreign entities that offer campaign help.

Republicans rejected Mr Trump's logic, flatly saying that such approaches should be reported, although they blocked a Democratic bid in the Senate to put that into law.

NYTIMES