The festive classic was streamed 9.2 million times over the last week, knocking LadBaby's Don't Stop Me Eating off the top spot.

First released in December 1984, George Michael and Andrew Ridgeley's song was held off the top spot by Band Aid's Do They Know It's Christmas?

Ridgeley said he was "somewhat amazed" the record had now reached number one.

He said he was "delighted" and "profoundly pleased" at the news, "albeit 36 years after its first release which is, perhaps more than anything, a testament to its timeless appeal and charm".

"It is a fitting tribute to George's song-writing genius and one of which he would have been immensely proud and utterly thrilled," Ridgeley added.

Since the song was released in 1984, it has returned to the top 10 a further six times.

Fans had previously launched a campaign to get it to number one in 2017, to mark the first anniversary of George Michael's untimely death on Christmas Day 2016.

But it only reached number two - and was thwarted by Ed Sheeran's Perfect.

Its lyrics also inspired Dame Emma Thompson to write the movie Last Christmas, which was released in cinemas last Christmas.

Last Christmas was written by George Michael in his childhood bedroom in February 1984, "and as far as I was concerned it was a number one", he told Smash Hits in 1986.

Inspiration struck out of the blue, while the singer was watching a football match at his parents' house in Hertfordshire.

"We'd had a bite to eat and were sitting together relaxing with the television on in the background when, almost unnoticed, George disappeared upstairs for an hour or so," recalled Ridgeley in his 2017 memoir.

"When he came back down, such was his excitement, it was as if he had discovered gold which, in a sense, he had.

"We went to his old room, the room in which we had spent hours as kids recording pastiches of radio shows and jingles... and he played me the introduction and the beguiling, wistful chorus melody to Last Christmas. It was a moment of wonder."

The song was subsequently recorded in the middle of August at London's Advision Studios, which Michael plastered in Christmas decorations to set the mood.

The cheesy-but-cheerful video was shot later that year in Switzerland, featuring Wham's backing singers Pepsi and Shirlie, model Kathy Hill, and Spandau Ballet's Martin Kemp - who was then dating his future wife Shirlie, so came along for the trip.

Alongside its famous chunky knitwear, and central role for a silver brooch, the video also marked the final time Michael would be seen without his trademark designer stubble.

The singer jetted back from the film shoot to record his vocals for Do They Know It's Christmas - which would eventually hold Wham!'s song off the top spot.

In a gesture of solidarity with Band Aid, however, the duo donated all the royalties from Last Christmas to Ethiopian famine relief.

At the time of its initial release, Last Christmas was part of a Wham! double A-side single, along with Everything She Wants.

Although immediately after Christmas, radio stations started playing Everything She Wants and the band did a Top of the Pops appearance to promote it, the colossal sales of Do They Know It's Christmas meant it was never to top the chart at the time.

Prior to today's chart, Last Christmas was the UK's biggest-selling single never to have reached number one - accumulating 1.9 million sales across its lifetime, according to the Official Chart Company.

That title now passes on to Maroon 5's Moves Like Jagger (1.55 million sales), which was a number two hit in 2011.

But Last Christmas does now hold a new chart record - for the longest time taken for a single to reach number one.

The previous record-holder was Tony Christie's (Is This The Way To) Amarillo? which had a 34-year gap between its original release and topping the chart for Comic Relief in 2005.

Wham!'s record is the second long-toothed classic to claim chart glory in recent weeks, after Mariah Carey's All I Want For Christmas Is You reached number one in December, 26 years after its release.

Christmas songs continue to dominate this week's chart countdown, with 28 festive tracks inside the top 40.

However, as festive streams decline, some other songs have seen their fortunes turn around - with Little Mix's Sweet Melody returning to the top 10; and Ed Sheeran's new single Afterglow reaching a new peak of 13.

In the albums chart, Michael Bublé's Christmas album returned to number one for the first time in nine years, displacing Paul McCartney's latest record, McCartney III.

Taylor Swift's second surprise album of 2020, Evermore, held steady at number two; while Dua Lipa's Future Nostalgia jumped 15 places to number three after featuring prominently in a number of end-of-year polls.

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