LONDON (REUTERS) - The man who will become the first British astronaut to visit the International Space Station said on Friday he hoped his mission would inspire young Britons to one day journey to Mars.

Tim Peake, 43, a former army major, will blast off on a six-month mission for the European Space Agency (ESA) in December - the first Briton to go into space since Helen Sharman travelled on a Soviet spacecraft for eight days in 1991.

"After a gap of 24 years since Helen Sharman flew to the Mir space station, the Union (Jack) flag is going to be flown and worn in space once again," Peake told reporters.

"What that means is that there's nothing to stop the schoolkids in Great Britain today from being amongst the first men and women to set on foot on Mars in the future."

Peake said he would be carrying out a series of scientific experiments, including some medical research where he would be a "human guinea pig".

The Briton, selected as an astronaut in 2009, will launch from Russia's Baikonur cosmodrome in Kazakhstan for the mission entitled Principia after Isaac Newton's ground-breaking Naturalis Principia Mathematica, which describes the principal laws of motion and gravity.

Britain originally opted out of the European programme for human space flight but decided to reverse its decision in 2012.

The space station is a laboratory in which an international crew of six people live and work while travelling at a speed of 8km per second, orbiting Earth every 90 minutes.

It was launched in 1998 and has been continuously occupied since November 2000.

In that time, more than 200 people from 15 countries have visited.