WASHINGTON • Mr Rudy Giuliani, US President Donald Trump's personal lawyer who has led the most extensive efforts to damage his client's political rivals and undermine the election results, discussed with him as recently as last week the possibility of receiving a pre-emptive pardon before Mr Trump leaves office, according to two people told of the discussion.

It was not clear who raised the topic.

Mr Trump has not indicated what he will do, one of the people said.

Mr Giuliani's potential criminal exposure is unclear. He was under investigation as recently as this summer by federal prosecutors in Manhattan for his business dealings in Ukraine and his role in ousting the American ambassador there, a plot that was at the heart of the impeachment of Mr Trump.

Mr Giuliani did not respond to a message seeking comment, but after a version of this article was published online, he attacked it on Twitter and said it was false.

Mr Giuliani's lawyer, Mr Robert Costello, said: "He's not concerned about this investigation because he didn't do anything wrong, and that's been our position from day one."

A spokesman for Mr Trump did not respond to an e-mail seeking comment.

Such a broad pardon pre-empting any charge or conviction is highly unusual but does have precedent. In the most famous example, president Gerald Ford pardoned Richard Nixon for all of his actions as president.

Mr Trump has wielded his clemency powers liberally in cases that resonate with him personally or for people who have a direct line to him through friends or family, while thousands of other cases await his review.

A pardon for Mr Giuliani, who has been involved in some of the President's most brazen acts, is certain to prompt accusations that Mr Trump has used his pardon power to obstruct investigations and insulate himself and his allies.

Mr Andrew Weissmann, a top prosecutor for special counsel Robert Mueller, has said that Mr Trump's dangling of pardons for his allies impeded their work.

In July, Mr Trump commuted the sentence of his longtime adviser Roger Stone, who had refused to cooperate with the special counsel's investigators and was eventually convicted of seven felonies.

Last week, Mr Trump pardoned his former national security adviser Michael Flynn, who had backed out of his cooperation agreement with the special counsel's office for "any and all possible offences" beyond the charge he had faced of lying to federal investigators.

The Flynn pardon raised expectations that Mr Trump would bestow clemency on other associates.

The President's discussions of a pardon for Mr Giuliani occurred as he has served as one of the loudest voices publicly pushing baseless claims of widespread election fraud that cost Mr Trump the election.

Mr Giuliani has expressed concern that any federal investigations of his conduct that appear to have been dormant under the Trump administration could be revived in a Biden administration, according to people who have spoken to him.

Legal experts say that if Mr Trump wants to fully protect Mr Giuliani from prosecution after he leaves office, the President would most likely have to detail what crimes he believed Mr Giuliani had committed in the language of the pardon.

Federal prosecutors in Manhattan have been investigating since last year the role of Mr Giuliani and two other associates in a wide-ranging pressure campaign directed at pushing the Ukrainian government to investigate Mr Trump's rivals, particularly the son of Mr Joe Biden. The two Giuliani associates - Lev Parnas and Igor Fruman - were arrested in October last year as they prepared to board a flight from Washington to Frankfurt with one-way tickets.

Parnas and Fruman were charged with violating campaign finance laws as part of a complex scheme to undermine the former American ambassador in Kiev, Ms Marie L. Yovanovitch, whom Mr Giuliani and Mr Trump believed should have been doing more to pressure the Ukrainians.

Prosecutors in Manhattan continued to investigate Mr Giuliani's role in the scheme over the past year, focusing on whether he was, in pushing to oust the US ambassador, essentially double dipping: working not only for Mr Trump but also for Ukrainian officials who wanted the envoy gone for their own reasons, according to people briefed on the matter.

NYTIMES