The government will publish maps of its preferred route accurate to five metres in urban areas and to 25 metres in rural districts, a Department for Transport spokesman said.
Britain only has 68 miles of high-speed rail, linking London to the Channel Tunnel subsea railway to France.
A 200 mph route would cut journey times to the north of Britain by half to just over two hours.
(Reporting by Tim Castle; editing by Elaine Hardcastle )