A New York judge on Tuesday delayed Donald Trump's sentencing for his conviction on criminal charges stemming from hush money paid to a porn star until Sept. 18, after the former U.S. president asked for a chance to argue he should have been immune from prosecution.

The sentencing had previously been set for July 11, just days before the Republican National Convention begins in Milwaukee on July 15. Trump is expected to be his party's nominee to challenge Democratic President Joe Biden in the Nov. 5 election.

Trump faces an uphill battle getting the hush money conviction overturned, since much of the conduct at issue in the case predated his time in office.

Trump's lawyers on Monday asked Justice Juan Merchan to allow them to argue that his conviction in New York state court in Manhattan should be overturned due to the U.S. Supreme Court's ruling on July 1 that presidents are entitled to immunity from criminal prosecution for official acts.

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Prosecutors with Manhattan District Attorney Alvin Bragg's office said Trump's argument was "without merit," but agreed to delay the sentencing to give him the chance to make his case.

A Manhattan jury on May 30 found Trump guilty of falsifying business records to cover up his former lawyer Michael Cohen's $130,000 US payment to adult film actress Stormy Daniels to stay quiet about her alleged 2006 sexual encounter with Trump until after the 2016 election, when Trump defeated Democrat Hillary Clinton.

Prosecutors said the payment was part of an illicit scheme to influence the election.

Trump denies he had sex with Daniels and has vowed to appeal the conviction after his sentencing.

In their letter to Merchan, defence lawyers argued that prosecutors had presented evidence involving Trump's official acts as president, including social media posts he made and conversations he had while in the White House.

Under the Supreme Court's ruling, prosecutors cannot use evidence related to official actions to help prove criminal cases involving unofficial actions.

"This official-acts evidence should never have been put before the jury," lawyers Todd Blanche and Emil Bove wrote.

Last year, Trump made a similar argument as part of an unsuccessful push to move the hush money case to federal court. In denying Trump's request in July 2023, U.S. District Judge Alvin Hellerstein wrote that the payment to Daniels "was a purely personal item."

"Hush money paid to an adult film star is not related to a president's official acts," Hellerstein wrote.

Trump's lawyers appealed Hellerstein's decision, but later abandoned the effort.

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Trial was 'rigged,' Trump says

Former U.S. president Donald Trump remained defiant after being found guilty on all 34 counts in his hush-money trial in New York, saying the trial was 'rigged' and a 'disgrace'