The London 2012 Olympics preparations have impressed the president of the International Olympic Committee (IOC).

IOC chief Jacques Rogge was given an status update on the planning stages by Prime Minister David Cameron, and was pleased with the reports.

"We can already see tangible results in the remarkable regeneration of East London. This great historical city has created a legacy blueprint for future Games hosts," he said.

"There is an economic legacy also. Tourism will get a boost and definitely there will also be a soft legacy; the enthusiasm of young kids to participate in sport."

Cameron pledged to deliver on promises of security and transport and a lasting legacy, and claimed that London will host "the greatest show on earth".

The 2012 Olympic Games opening ceremony takes place in London on July 27.