The Democrats are split over whether Donald Trump should be impeached after the Mueller Report. (Reuters)

US President Donald Trump said in an interview broadcast Sunday his chances of retaining the White House in 2020 would be strengthened if Democratic lawmakers start impeachment proceedings against him.

Asked on NBC's "Meet the Press" whether he thought impeachment was good politics for him, Trump replied, "I think I win the election easier."

The president repeated his longstanding allegation that the FBI's counterintelligence investigation into his 2016 campaign was illegal.

"I was spied on. What they did to me was illegal. It was illegal on the other side. I did nothing wrong," he said.

"So impeachment's a very unfair thing because nothing that I did was wrong. And if you look at the Mueller report, there was no collusion. This was all about collusion."

The Democrats are split over whether Trump should be impeached after the Mueller Report into Russian interference in the 2016 election outlined numerous contacts between his campaign and Russians, as well as evidence that the president tried on several occasions to stymie the investigation.

While many of the candidates for the Democratic nomination are pro-impeachment, House Speaker Nancy Pelosi has argued that it would be a risky move without an "ironclad" case and bipartisan support.

Trump told "Meet the Press" Pelosi was staving off growing impeachment calls from within the Democratic caucus because she agreed with his assessment that it would harm their prospects in 2020.

"I think she feels that I will win much easier," Trump said. "I mean, I've been told that by many people."

Former special counsel Robert Mueller spent nearly two years investigating Russian election interference and possible involvement by Trump and his inner circle.

He concluded that there wasn't sufficient proof of a criminal conspiracy but found that Trump's campaign welcomed and expected to benefit electorally from information stolen and released through Russian efforts.

If the Democrat-controlled House of Representatives were to vote on formal impeachment charges, the Republican-held Senate would decide whether to convict, which requires an unlikely two-thirds majority.