The Republican nominee also urged his supporters to ‘watch’ cities with big African American populations on election day to prevent a ‘rigged’ election

Donald Trump has said he would use the US presidency to impose term limits on members of Congress as part of a drive to “drain the swamp” of Washington corruption.

Currently, House members can serve an unlimited number of two-year terms, while senators can serve an unlimited number of six-year terms. The Republican candidate told cheering supporters in Grand Junction, Colorado, that he would push for a constitutional amendment.

“Six years for members of the House and 12 years for members of the Senate,” Trump said at the rally in an airplane hangar. “Collusion must and will come to an end. It’s time to sweep the corruption out of Washington.”

Trump on Monday issued a five-point plan for “ethics reform” in government to underline his status as an outsider taking on the political establishment, which he claims Hillary Clinton personifies.

The celebrity billionaire’s pledge came as he warmed up for Wednesday’s third and final presidential debate with Clinton in Las Vegas, needing a convincing performance to change a race that seems to be inexorably slipping away.

Trump also spoke in racially charged terms as he defiantly reiterated his warning about potential voting fraud. He urged his supporters to “watch” cities with big African American populations on election day to prevent a “rigged” election.

“They even want to rig the election at the polling booths,” Trump said. “Take a look at St Louis. Take a look at Philadelphia. Take a look at Chicago. Look. Look. If nothing else, people are gonna be watching on November 8. Watch St Louis. Watch Philadelphia. Watch Chicago.”

The remarks came hours after Barack Obama scolded Trump for making the groundless claims that subvert traditions of American democracy, insisting that he had no evidence.

Obama calls Trump's 'rigged' election claims irresponsible 'whining' Read more

“I have never seen in my lifetime or in modern political history any presidential candidate trying to discredit the elections and the election process before votes have even taken place,” the president said. “It’s unprecedented. It happens to be based on no facts.”

He said of Trump: “If you start whining before the game is even over, if whenever things are going badly for you and you lose you start blaming somebody else, then you don’t have what it takes to be in this job.”

As the president spoke, he lifted his left hand and pointed, with his thumb, over his shoulder to the Oval Office. He then added: “I’d advise Mr Trump to stop whining and go try to make his case to get votes.”

Obama also took a swipe at Trump for praising Russian President Vladimir Putin and was especially critical of Republicans who have fallen into line and done the same.

Earlier on Tuesday one of Trump’s last loyal supporters, New Jersey Governor Chris Christie, came out against his claims of rigging. “I am convinced that the election will be a fair one and the process will be one that will be accepted by the American people,” Christie said.

Along with polling station fraud, Trump argues that the media is colluding with Clinton by reporting that multiple women accused him of sexually assaulting them.

“The media, you have to remember, is an extension of the Hillary Clinton campaign,” he said in Grand Junction. “They so poison the minds of the public by writing false stories. I believe they are more crooked than Crooked Hillary. That’s a lot.”

At an earlier rally in Colorado Springs, Colorado, he urged his followers to “forget the press, read the internet, study other things, don’t go for the mainstream media”.

Trump blames media after more sexual misconduct accusations reported Read more

His running mate Mike Pence, speaking in Wilmington, North Carolina, claimed that the election is not “exactly a fair fight” because “the media out there is doing half of Hillary Clinton’s work for her every day”.

At least two protesters were ejected from Trump’s rally in Grand Junction. As the crowd erupted angrily and chanted “USA, USA”, he claimed the demonstrators were “professionals” who were paid $1,500 and given an iPhone.

“Can you get paid for doing this by the Democratic National Committee?” he said. “Maybe I’ll do it a couple of times. It’s good money.”

Recent opinion polls show Clinton ahead or tied in most of the key battlegrounds that Trump needs to win if he is to pull off a surprise comeback before 8 November. A new SurveyMonkey poll of 15 battleground states conducted with the Washington Post showed Clinton leading in enough states to put her comfortably over the majority needed to win the presidential election.

Billionaire Mark Cuban and Hewlett Packard Enterprise chief executive Meg Whitman will attend Wednesday’s last presidential debate as guests of Clinton.

Trump’s campaign has invited Pat Smith, whose son, Sean, was one of four Americans killed during the 2012 attack on the US compound in Benghazi, Libya, when Clinton was secretary of state. Smith has said she holds Clinton personally responsible for her son’s death.