'Maggie May' singer Sir Rod Stewart announced that his 'friend' Donald Trump isn't presidential material after being knighted by Prince William on Tuesday.

The 71-year-old 'Do Ya Think I'm Sexy?' star was asked about the Republican hopeful by press at Buckingham Palace.

'Although he's sort of a friend of mine, I don't think he's presidential,' Sir Rod said. 'I don't think he's made to be a president.'

Old friends: Trump and Stewart (pictured in 1980 with Stewart's then-wife Rachel Hunter and record producer Clive Davis) have known each other for decades

'Not presidential': But on Tuesday, Stewart said Trump (pictured together with Kenny G at Trump's Mar-a-Lago estate in 1998) was 'not presidential' and 'isn't made to be president'

Knight: The remarks came after Stewart, 71, was given a knighthood by Prince William. Stewart had declined to answer questions about 'friend' Donald Trump last year

The pop star, who was knighted for services to music and charity, had ducked a question about Trump in October last year, during an interview with Billboard.

While being interviewed about his 29th solo album, 'Another Country', Stewart was asked 'How do you feel about the US presidential campaign?'

'What the f*** does that have to do with my album?' he replied. 'I have strong political beliefs, and I don't want to get into it. Donald Trump happens to be a friend of mine.'

It's not known why he allowed himself to be drawn on the topic today - or why he's downgraded Trump to 'sort-of-friend.'

Stewart does indeed have a long history with Trump, 70.

He and second wife Rachel Hunter were pictured with the property mogul at a shindig in 1980.

And Stewart and Trump appeared again alongside saxophonist Kenny G in a photo taken at Trump's Palm Beach club, Mar-a-Lago, in 1998.

More recently, Trump posted a picture of the two together at Mar-a-Lago on Facebook in 2013 - although it has since been deleted. It's not known whether the photo was deleted before or after Stewart's remarks on Tuesday.

Trump also tweeted 'Rod, album is great!' while linking to the Billboard article in which Stewart defended his pal's honor.

And just last year the singer made an appearance, along with current wife Penny Lancaster, at Trump's New Year's Eve party in Mar-a-Lago.

Not that he had to travel far for the party - the newly knighted star lives in a mansion close to the famous club.

Pals: Trump posted a picture of him and Steward at his Mar-a-Lago club in 2013 on Facebook, though the image has been taken down. It's not clear if it was removed after Stewart's remark

Support: Trump wrote this tweet in October 2015, linking to the article in which Stewart refused to comment on Trump's campaign. He also commended Stewart's new album

Stewart didn't just talk about Trump after his knighthood ceremony, however: he also appeared to make a sly dig at Clinton.

He joked that there were seven women in his new band - 'more than there are in the White House.'

Accompanied by Lancaster and their two sons, Alastair, 10, and five-year-old Aiden, Stewart said he wished his parents could have been there to see him as he was congratulated by Prince Wiliam, the Duke of Cambridge.

Receiving the honour left him 'on cloud nine', he said.

Wearing tartan trousers, he said of meeting William: 'We talked about music and he said "It's great that you're still going" and I said: "I have to - I've got eight children!".'

Ceremony: Rod Stewart is knighted by the Duke of Cambridge on Tuesday. He said the experience left him 'on cloud nine'

Others awarded in the ceremony were British-Nigerian actor David Oyelowo, who starred as Martin Luther King Jr in 'Selma'. He was made an Officer of the Most Excellent Order of the British Empire (OBE) for his services to drama.

Others honored include Vanessa Kingori, first black female publisher of British GQ, for services to the media industry, and Professor Nick Webborn, for services to paralympic sports medicine and the British Paralympic Association.

Some 86 recipients attended the ceremony at Buckingham Palace, proudly watched by 265 guests, including family and friends.

Songs including 'Imagine' by John Lennon and Abba's 'Mamma Mia' were played by the background orchestra to accompany the service.