Former world boxing champion Muhammad Ali signs for the pupils in the 1st Experimental Elementary School of Beijing on Feb. 25, 1993 when he is invited as a guest for the Beijing International Boxing Champions Meet. (Xinhua/Guan Tianyi)

WASHINGTON, June 8 (Xinhua) -- U.S. President Donald Trump on Friday entertained the idea of pardoning deceased boxer Muhammad Ali, but Ali's lawyer said the gesture was "unnecessary" as Ali's conviction was overturned.

Trump remarked before departing for the G7 summit that he is considering pardoning a number of people, including Ali, who was sentenced to five years in prison after refusing to fight in the Vietnam war citing religious objections.

"He wasn't very popular then, he certainly is, his memory is very popular now, I'm thinking about Ali, I'm thinking about that very seriously," he said.

"And some other, and some folks that have sentences that aren't fair," Trump added.

In response to Trump's comment, Ali's lawyer Ron Tweel said in a statement that while Trump's sentiment was appreciated, a pardon is "unnecessary."

"The U.S Supreme Court overturned the conviction of Ali in a unanimous decision in 1971. There is no conviction from which a pardon is needed," the statement said.

Trump has been keen to exercise his power to pardon or commute sentences in recent weeks. Earlier this week he commuted the sentence of 63-year-old Alice Johnson, who was sentenced to life in prison for drug related crimes in the 1990s, partly as the result of strong lobbying efforts by celebrity Kim Kardashian.

Trump has also touted on twitter that he had "absolute power" to pardon himself, prompting the White House press office to clarify that it wouldn't be necessary for Trump to do so because he had done "nothing wrong."

Analysts believe Trump's newfound enthusiasm for exercising pardoning power is because it's a presidential privilege unchecked by other branches of government, which cannot be said of most of Trump's other policies.