These are the pictures that prove Amy Winehouse is fit and ready for Nelson Mandela’s 90th birthday concert in Hyde Park tonight.

The troubled singer has been the subject of a 'will she, won’t she' debate as she battles back to health following her collapse last week.

It was feared she would miss both the Mandela show and Glastonbury this weekend after doctors said she was showing the early signs of emphysema.

Rehearsal: Amy Winehouse takes part in a sound check ahead of her appearance at Nelson Mandela's 90th birthday concert tonight

But she put in an impressive performance on stage yesterday, belting her way through Rehab, Valerie and a version of Free Nelson Mandela with the Soweto Gospel Choir.

Amy  is being tipped to perform Free Nelson Mandela tonight, alongside its composer Jerry Dammers.

The song was released in 1984 in protest about Mr Mandela's imprisonment.

It was performed at Nelson Mandela's 70th birthday concert at Wembley Stadium London in 1988 and became an anthem for the anti-apartheid movement in UK.

A source at the rehearsals said: 'She was very perky and was joking on with her band and sound team.

'This was the old Amy, and she is clearly keen to just get up on stage and do what she does.

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Sound check: Amy Winehouse belted out a rendition of Free Nelson Mandela

'She is starting to get very bored in the clinic where she is being treated after her collapse, so is very much looking forward to her two performances.

'The whole place stood still when she took to the stage  - security guards, sound engineers, lighting people  -  everyone just stopped in their tracks to watch her perform. She is looking on top form.'

Amy is also excited at the prospect of having a dressing room next to the show's host, Will Smith.

Our source adds: 'She was asking everyone where Will was at the rehearsal and can't wait to meet him tonight. She's a big fan.'

Other acts at the concert, which is being shown on ITV at 9pm, are Queen, Annie Lennox and Leona Lewis.

She spent an hour-and-a-half in rehearsals, but did not turn up to a photocall on Thursday and also snubbed an invitation to Mandela's 90th birthday party dinner on Wednesday night.

On the way to rehearsals she paid a visit to husband Blake Fielder-Civil at London's Pentonville Prison, before stopping off at an off licence for some Jack Daniels whisky and vodka.

Amy is also lined-up to take part in a spectacular Glastonbury supergroup performance.

Headliner Jay-Z has invited the 24-year-old to join him on stage alongside A-list stars Beyonce, Chris Martin and Rolling Stones guitarist Keith Richards.

Festival organiser Michael Eavis is said to be looking forward to Amy's performance and has even offered a helicopter to fly her to the site in Somerset.

A source told the Mirror newspaper: 'Jay-Z wants an amazing headline show and has gone through his address book to ask famous friends to join him.

'He thinks Amy is fantastic and thought it would be the perfect chance to work with her.'

Supergroup: Amy has been invited to sing alongside Jay-Z, Beyonce and Chris Martin at Glastonbury