British Prime Minister has said Qatar should follow the example of London's construction of 2012 London Olympic venues, in which no lives were lost, when building sites for the 2022 football World Cup.

"My message is that they ought to insist on better," Cameron said following reports migrant workers were dying on building sites for the 2022 tournament.

"We in the Olympics, I think I'm right in saying, managed to build that entire Olympic Park with the best ever record on safety - no-one dying during construction, keeping injuries to an absolute minimum," Cameron also told BBC Radio 5 Live on Tuesday.

"It can be done. The British construction industry we really can hold up as a good example to the rest of the world. That gives us an advantage in saying to the rest of the world 'We'll come and build some of your infrastructure'.

"This was an area we were bad at in the past and I think everyone has a duty to insist on the best safety standards."

However, the Chairman of Qatar's National Human Rights Committee (NHRC) on Monday denied claims by Britain's Guardian newspaper that 2022 World Cup organisers were treating Nepalese construction workers like 'slaves'.

Ali Al-Marri said the allegations, made last week, were totally erroneous.

"There is no slavery or forced labour in Qatar," he said at a press conference.

"The information that The Guardian reported is false and the numbers cited by them are exaggerated."

The Guardian report last Thursday said dozens of Nepalese workers have died while working in Qatar in recent weeks, raising concerns about the Gulf state's preparations to host the World Cup.

Quoting documents obtained by the Nepalese embassy in the Qatari capital Doha, the Guardian said thousands of Nepalese -- at 370,000 the second largest group of labourers in Qatar after the Indians -- faced exploitation and abuses amounting to "modern-day slavery".

Marri admitted there had been difficulties but added the government were doing their utmost to put these right.

"There have been some problems, owing to the fact that there are 44,000 businesses in the country," he said.

"But I can assure you that the authorities are constantly making efforts to resolve the problems."

Aidan McQuade, director of Anti-Slavery International, who has seen the documents presented by the newspaper, told AFP last Thursday the evidence was "certainly highly indicative of a brutal working environment which is not good for anybody."

Ali Ahmad Al-Khalifi, advisor on international relations to the Qatari Ministry of Work, told AFP that as a result of the Guardian article they were going to double the number of Work Inspectors to 150 in order that no abuses of workers takes place in the future.

For its part the International Confederation of Trade Unions (ITUC) estimated that at the rate of deaths on building works in Qatar, at least 4000 workers will die before the World Cup begins.

The ITUC is due to send a delegation to Qatar on October 7 in order to observe the working conditions for migrants in the country.