David Beckham has been accused of writing a 'furious' email to his PR after learning that Katherine Jenkins had been awarded an OBE.

Hackers released several emails said to have been written by the footballer, which include a mention of the classical singer that suggests Beckham was angry to learn she had received an OBE and that he had yet to receive a knighthood from the Queen.

According to The Sun, which cites a number of European media outlets, Beckham sent an email to his longtime PR Simon Oliveira in 2013, which allegedly said: "Katherine Jenkins OBE for what? Singing at the rugby and going to see the troops plus taking coke. F***ing joke."

Jenkins has previously admitted in interviews to taking cocaine when she was younger, saying "curiosity got the better of me".

Katherine Jenkins with her partner Andrew Levitas, holding her OBE medal outside Buckingham Palace in 2014 (Getty)

Oliveira told The Independent that the emails had been "hacked and doctored" from a private account.

"This story is based on outdated material taken out of context from hacked and doctored private emails from a third party server and gives a deliberately inaccurate picture," he said.

"David Beckham and UNICEF have had a powerful partnership in support of children for over 15 years. The David Beckham 7 Fund specifically has raised millions of pounds and helped millions of vulnerable children around the world. David Beckham has given significant time and energy and has made personal financial donations to the 7 Fund and this commitment will continue long term."

The Sun has suggested that the leak threatens to undermine Beckham's charitable work.

UNICEF, a charity which Beckham has been a Goodwill Ambassador for since 2005, has issued a statement supporting him, but a spokesperson also said they were "looking in to" the reports.

"UNICEF has become aware of media reports relating to 7: the David Beckham Fund for UNICEF," the statement read.

"Some reports relate to alleged private correspondence between our ambassador and other parties, which we have not seen and cannot comment upon.

David Beckham's Unicef charity match Show all 16 1 /16 David Beckham's Unicef charity match David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 Luis Figo's shirt is laid out ahead of kick-off. 2015 Manchester United FC David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 Sir Alex Ferguson arrives at Old Trafford to manager team GB &Ireland 2015 Manchester United FC David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 David Beckham arrives with a smile for the cameras. 2015 Manchester United FC David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 Phil Neville points out a familiar face as he returns to Old Trafford. 2015 Manchester United FC David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 The players pay their respects to the victims of the Paris terrorist attack. 2015 Getty Images David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 Referee Pierluigi Collina addresses David Beckham and Luis Figo ahead of kick-off. 2015 Manchester United FC David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 Paul Scholes heads in the first goal of the game after a cross from David Beckham. 2015 Getty Images David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 David Beckham smiles as he carries the ball in the pouring rain. 2015 Getty Images David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 Nicky Butt is carried off the pitch on a stretcher after suffering a torn Achilles. 2015 Getty Images David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 Peter Crouch attempts an acrobatic effort on goal. 2015 Getty Images David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 Michael Owen powers in the second goal of the game. 2015 Manchester United FC David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 The Rest of the World celebrate after Dwight Yorke scores. 2015 Getty Images David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 Michael Owen bags his second goal of the game after an error from replacement goalkeeper Raimond van der Gouw. 2015 Manchester United FC David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 Carlo Ancelotti and Sir Alex Ferguson share a joke after the full-time whistle. 2015 Manchester United FC David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 David Beckham hugs his son Brooklyn after the match. 2015 Manchester United FC David Beckham's Unicef charity match GB & Ireland 3 Rest of the World XI 1 Team GB & Ireland beat the Rest of the World XI 3-1. 2015 Manchester United FC

"David Beckham has been a UNICEF Goodwill Ambassador since 2005, and as well as generously giving his time, energy and support to help raise awareness and funds for UNICEF’s work for children, David has given significant funds personally. The 7 fund supports programmes for children, tackling issues such as malnutrition, violence, AIDS and emergencies.

"For example, in June 2016 David visited Swaziland to raise awareness of the devastating drought affecting Eastern and Southern Africa, helping UNICEF reach people around the world with important messages about the need for urgent action."

The statement went onto list some of the work Beckham has done for UNICEF.