The 27-year-old, who announced her retirement from the music scene two years ago, joined the Hackney rapper on stage for a rendition of their 2010 hit, ‘Just Be Good To Green,’ in front of the packed 75,000 crowd.

The ‘LDN’ star, who last week revealed she was working in the studio with producer Greg Kurstin, had hinted at her return in a tweet posted before the gig:

“Right, so what was the ground like at Heaton park, do I need Wellies ?”

After the show, she then took to the same social networking site to joke about her first live outing in two years:

“No @professorgreen wasnt swinging a cat around on stage @HEATON PARK that was me trying to sing. loved it , thanks manchester x x x"

The 27-year-old, who last night performed at Radio 1’s Hackney Weekend as the Special Guest, told the Daily Star that he’s flattered but puzzled that he’s held in such high regard by the likes of Tinie Tempah and Professor Green:

“I don’t know how I’ve got this tag as ‘the urban godfather’ because I just do my thing. It’s an honour if people see me as an inspiration but when I’m in the studio it’s all about what my next step is.

“If Pass Out by Tinie comes on in a club, I’m right there on the dancefloor. I’m not thinking: ‘Hmm, has my music inspired him?’”

The ‘Bonkers’ star, who recently re-recorded his cover of Tears For Fears’ Shout for England’s Euro 2012 campaign, also revealed that while he may have been quiet of late, he’s been busy working on the follow-up to 2009’s  ‘Tongue ‘N’ Cheek.’

“I’ve been out of the game but as well as chilling I’ve been constantly working on the album.

“It’s only other people who think I’ve been away, as I’ve still been busy.”

The 'Read All About It' hitmaker told MTV News that despite having been a couple since February of this year, the attention they attract when out in public together is still intense and they have to learn to ignore it because they want to live their lives:

"Do you know what? I kind of got into it naïvely not expecting that to happen and it has. They [the press] have really sunk their teeth into it. In a sense, I suppose we’ve fuelled it but by doing things that are unavoidable, like normal things that people do in a relationship, like going shopping."

"I support her in what she does. You know, I went to the BAFTAs with her and she supports me with what I do, she came to The Brits with me. We understand that we are going to get photographed, that’s obvious."

He also admitted that certain publications have created false stories about them and they've been forced to accept gossip as a by-product of fame:

"The thing is, we don’t talk to these weekly magazines. You haven’t seen us in OK! magazine and no, you will not. They just pull things out of thin air or they take one line and they fluff it up."

"I see headlines and then I read what’s beneath them and what they’ve used as a headline hasn’t even been said. It’s just something they’ve made up. It’s a bit of a wind up."

Watch his latest music video below:

The star-studded event takes place over August 18 and 19 at Hylands Park, Essex and Weston Park, Staffordshire.

Tulisa is replacing US acoustic act Lissie on the bill, who has pulled out.

She joins already announced acts such as headliners the Stone Roses and The Killers.

The impressive line-up also sees the likes of Nicki Minaj, Example and Professor Green all set to perform.

She will be sharing the bill with fellow N-Dubz alumni Dappy and also Rita Ora, who joined Tulisa as a guest judge on the X Factor recently.

As previously reported, the rapper took part in the UK's first ever VEVO Go Show recently, which encourages acts to perform in unusual locations.

Green took to London's busy Carnaby Street to play a rendition of his track 'Remedy' to surprised onlookers.

In the video, which was posted online today (June 6), Green says he chose the London street because he used to freestyle at open mic nights there.

The rapper meanwhile has been busy defending his relationship to Made In Chelsea's Millie Mackintosh, claiming that they are often subject to class prejudice from outsiders.

The 28-year-old will walk away with £100,000 and a record deal with Universal Records after renditions of James Brown’s ‘It’s A Man’s Man’s Man’s World’ and ‘Mama Told Me Not To Come,’ the latter of which was performed with coach Tom Jones, helped her to scoop victory in the BBC final.

Tyler James, who teamed up with mentor will.i.am on Usher’s ‘OMG’ as well as covering The Jackson 5’s ‘I’ll Be There,’ and Bo Bruce, who tackled Professor Green’s 'Read All About It' with The Script’s Danny O’Donoghue and Sinead O Connor’s 'Nothing Compares 2 U,' finished in the top three; while Vince Kidd, who duetted with Jessie J on her hit, ‘Nobody’s Perfect,’ and sang Jimmy Cliff’s ‘Many Rivers To Cross,’ placed fourth. 

The four coaches also appeared on stage together again in a medley which included Jessie J’s ‘Price Tag,’ The Script’s ‘Breakeven,’ Tom Jones’ ‘It’s Not Unusual’ and The Black Eyed Peas’ ‘Where Is The Love,’ whilst Maroon 5 and Ed Sheeran also performed their new singles during the two-hour show. 

The rapper was taking part in a webchat with The Sun when he was asked what he would do if he was Prime Minister for Great Britain. Green - who is dating Made In Chelsea's Millie Mackintosh - replied:

"I'd put all of Towie in prison. Or maybe I'd kill them all and the country’s IQ would rise."

He added: "Only joking!"

Green also made reference to The Only Way Is Essex's former leading light Amy Childs, adding:

"Amy Childs was at the Baftas presenting an award. Comedy’s all about timing and there were some awkward sketches..."

Green has recently discussed the frustration he experiences over people's reaction to he and Millie Mackintosh's relationship, citing class prejudice.