England's bid for the 2018 World Cup has been thrown into another crisis by the shock resignation of Sir Dave Richards from the board.

Richards has sent a letter to Lord Triesman, chairman of the bid and the Football Association, saying that he would continue to support the campaign but no longer wanted to be on the board.

The resignation comes as a devastating blow to bid leaders, and especially to Triesman, who had hoped to draw a line under recent turmoil by streamlining the board at an emergency meeting 10 days ago.

Richards said in a statement released to Press Association Sport: "With the recent changes to the England 2018 bid team structure, I feel I can now best support a successful bid without the necessity of sitting on the board.

"My positions as Premier League chairman, FA board member and chairman of the FA's international committee provide me with ample opportunities to bang the drum for English football, and the bid particularly, right across the world, which I will continue to do wherever and whenever I can.

"My belief is that England has all the right attributes to host a successful FIFA World Cup, our challenge now is to convince the 24 members of FIFA's ExCo [executive committee] of that. This must be our focus and priority going forward."

The shock move highlights the underlying tensions between the Premier League and the FA which have existed since Triesman made a public attack on clubs' debts in October 2008.

Richards and Premier League chief executive Richard Scudamore were both ignored when Triesman initially put the bid board together before, on the insistence of bid chief executive Andy Anson, Richards was persuaded to join so the campaign could harness the international clout of the Premier League.

Richards' main value is in the form of his international contacts, particularly in Africa and Asia.

Sports minister Gerry Sutcliffe, who himself agreed to step down from the board the week before last to give it more of a football focus, expressed his disappointment.

Sutcliffe told Press Association Sport: "I'm sad about that and disappointed.

"Dave Richards has great skills and contacts around the world so I'm pleased he will still be in contact with the bid.

"We had hoped to create a more football-focused board so I hope someone else to represent the Premier League will now go on the board in his place."

Richards' resignation is the most serious development in several weeks of turmoil for the bid, first sparked by outspoken criticism of the campaign by FIFA vice-president Jack Warner.

This was followed by revelations that the bid were giving designer handbags to the wives of FIFA members.

Warner returned the gift, angry that his wife had been exposed to embarrassment, and sent a furious letter to Triesman.

Some board members and the Government became increasingly concerned at the direction of the bid and this led to a crisis meeting on November 12 where a seven-man streamlined board was announced.

This included FIFA vice-president Geoff Thompson for the first time and included Triesman, Richards, Football League chairman Lord Mawhinney, Lord Sebastian Coe, Paul Elliott and Anson.

Original board members such as David Gill, Sir Keith Mills and Sutcliffe joined an advisory group headed by Karren Brady.

In response to Richards' resignation, England 2018 released a statement from Anson insisting it was a personal decision and "not a Premier League issue".

Anson said: "This was a personal decision by Sir Dave but he will continue to support the World Cup bid and use his wealth of international experience to support the campaign.

"He clearly remains committed to helping England win and he'll continue to go around the world lobbying on our behalf. This is not a Premier League issue. Sir Dave has made his own decision about his place on the board, so we've accepted his resignation and we move on.

"I've spoken to Richard Scudamore and David Gill who are out in Kuala Lumpur with Peter Kenyon working for the Premier League and supporting the bid.

"They are fully behind what we're doing and it was encouraging to hear that being emphasised.

"They have done some excellent work on our behalf around Asia on their current trip so this not an issue about the Premier League."

Anson said the bid was now focused on the decision for the host candidate cities, which will be announced on Thursday, and next week's presentations in Cape Town.

He added: "There is so much that's good going on at the moment, with host city submissions this week and David Beckham supporting us in South Africa next week.

"We have to focus on moving forward with the bid and utilise the support of Sir Dave and many others to make this a successful campaign.

"We have the support of fans across the country and we firmly believe we have the credentials."

Sir Dave Richards Factfile

Runs a group of companies involved in engineering, telecommunications and water and waste treatment before becoming involved in football.

1990: Appointed chairman of Sheffield Wednesday.

The club are relegated from the old First Division in 1989-90, but bounce back immediately to the top flight in the following season, also winning the League Cup.

August 1992: The Owls, under Richards' leadership, are founder members of the Premier League.

April 1999: Appointed chairman of the Premier League.

2000: February - Stands down as Wednesday chairman.

2003: March 31 - Succeeds Lord Pendry as chairman of the Football Foundation, a charitable organisation looking to improve grass-roots football.

2006: February 2 - FA board agree that Richards, as vice-chairman of the International Committee, will form a three-man panel along with International Committee chairman Noel White and FA chief executive Brian Barwick to select the next England manager.

February 10 - Richards is quoted saying the next England manager "should be British". In May, Englishman Steve McClaren is named as the next national team boss.

Richards is one of four Premier League representatives on the FA's main board.

June 17 - Receives knighthood in Queen's Birthday Honours for services to sport.

July - Cleared over allegations of covering up illegal payments while at Sheffield Wednesday.

2007: As vice-chairman of the FA international committee, takes part in decision to sack McClaren as England manager and appoint Fabio Capello.

2008: Appointed chairman of FA's international committee.

2009: March 19 - Joins England's 2018 World Cup bid as deputy chairman, with specific international relations remit.

June - Denies link to a takeover of Portsmouth.

November 24 - Resigns position on England's 2018 World Cup board, saying: "I feel I can now best support a successful bid without the necessity of sitting on the board."