Andy Hunt, the chief executive of the British Olympic Association (BOA), claimed today that increased competition from abroad meant it would be more difficult for the team to match its achievement in Beijing in 2008 when they finished fourth overall behind superpowers China, the United States and Russia and ahead of Australia for the first time in 20 years.

He said: "I'm not saying we won't achieve fourth but my aspiration today, two years out, is top six.

"As we go through the journey I hope to share that increased comfort in achieving what we achieved in Beijing."

But UK Sport, publishing its latest Mission 2012 assessment, claimed that they were confident the success achieved in Beijing would be maintained at London.

Outgoing UK Sport chief executive John Steele said: "We are continuing to see British elite level sport rise to the challenge that comes with a home Games.

"With just over two years to go until the start of the London Olympics, our Mission 2012 tracker board shows that as a result of targeted investment and the hard work of athletes, coaches and support staff, we are on track to achieve our targets.

"Successful British athletes in London will not only inspire a generation of young sportsmen and women in this country, but will also be a key indicator as to whether we have hosted a successful Games.

"The progress we are making makes me confident that we will deliver when it matters in two years time."

Britain improved from tenth at Athens in 2004 to fourth in Beijing with a total of 47 medals, including 19 gold, Britain's best-ever performance in an overseas Games.

Some sports have already competed in their UK Sport target event for 2010, with results supporting the feedback given through Mission 2012, whilst other sports, such as athletics and swimming, have key events coming in the next couple of months, Steele said.

Steele pointed to the fact that sports like cycling and boxing have continued to show that they are capable of performing at the highest level with cycling winning eight medals at the Track World Championships and boxing winning five medals in their target event, the European Championships, their best performance for nearly half-a-century.

There has also been a recent spate of firsts in Olympic sports over the past couple of months with the women’s hockey team winning their first ever medal in the Champions Trophy and Modern Pentathlon winning their first ever men’s individual medal at the European Championships.

Steele said: "In 2010 we have already seen the likes of boxing, which had red elements leading into Beijing, have their best result in a European Championships for almost 50 years and sports such as triathlon, canoeing and gymnastics having current World or European champions within their squads.

"Mission 2012 suggests that these high level results will continue throughout 2010 and I am optimistic that, with two years to go, British sport could not be in a better position to succeed."

Sports and Olympics Minister Hugh Robertson was also upbeat about Britain's chances at London.

He said: "Following our success in the medal table in Beijing, it is encouraging that British athletes continue to perform strongly.

"As the host nation in 2012, we have an unrivalled opportunity to transform sport in this country and every time our sportsmen and women step up onto the podium they can inspire people to get more active.

"I am encouraged by sports’ progress and am confident that our athletes will be at the top of their game in 2012."

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