Mr Trump said the pair talked about "life", while West later said the meeting was about "multicultural issues".

West, who recently cancelled shows on his Saint Pablo tour and was reportedly hospitalised for exhaustion following some erratic on-stage behaviour, entered the lobby of the Manhattan building just after 9am. He and the President-elect came down to the lobby less than an hour later to pose for pictures together.

West's visit comes as Mr Trump on Tuesday confirmed ExxonMobil CEO Rex Tillerson as his pick for Secretary of State and one day after senior Republicans backed an investigation into reports that the CIA believed Russia had deliberately interfered with the presidential election, releasing hacked information to damage Hillary Clinton's campaign. On Tuesday he also announced former Texas governor Rick Perry as his choice to lead the Energy Department, which Mr Perry had once promised to abolish.

Mr Trump has not held a press conference since he was elected president and only the night before had reiterated a pledge to do this in the "near future" but said these were "busy times!". But he nevertheless made the time to meet with West and then speak very briefly to reporters as he posed with him in the lobby.

"Just friends, just friends, he's a good man," the President-elect said, pointing at West. "We've been friends for a long time."

Asked what they discussed, Mr Trump responded "life".

Several hours after the meeting, West sent out a series of tweets about the meeting, saying "I wanted to meet with Trump today to discuss multicultural issues":

At Trump Tower, reporters tried to ask West a series of questions about why he was there but the star simply responded "I just want to take a picture right now."

Mr Trump's spokeswoman Hope Hicks told CNN that it was West who had requested the meeting with the President-elect.

There is ongoing speculation in the US about which singers or bands will perform at Mr Trump's inauguration in January. A member of his team had floated Elton John's name last month, but the British singer shot down that report and said he would not be playing.

Mrs Clinton received high profile support on the campaign trail from a range of performers, including superstar couple Beyoncé and Jay Z. West and Jay Z are former collaborators and West famously ran on stage at the 2009 MTV awards while Taylor Swift was accepting an award to declare that Beyoncé had made "one of the best videos of all time".

But the relationship between West, who is married to reality star mogul Kim Kardashian, and the couple seems to have deteriorated, with West criticising Beyoncé and accusing her of "playing politics" at the 2016 MTV Awards during the same on-stage rant in which he declared his support for Mr Trump.

The meeting with Trump is not West's first brush with politics. In the aftermath of Hurricane Katrina in 2005, West went off-prompter during a live telethon saying he hated the way the media was portraying African-American victims of the disaster as "looters" and declared then-president George W. Bush "doesn't care about black people".

Earlier this year, he declared he would run for president in 2020. Later on Tuesday, he tweeted the hashtag #2024, perhaps hinting he had reassessed the timeline of his presidential ambitions.

Mr Trump was also due to meet with Microsoft founder and philanthropist Bill Gates later on Tuesday, ahead of a technology summit he is hosting on Wednesday.