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LONDON, Feb 11 (Reuters) - British Prime Minister Boris Johnson gave the green light for a high speed rail project connecting London to northern England on Tuesday, saying he would take a firmer grip on a project that is behind schedule and running billions of pounds over budget.
Known as HS2, the high speed line will slash journey times and add capacity to Britain's crowded network, allowing the UK to catch up with countries like France and Spain which have extensive high-speed rail.
Johnson, who secured a crushing election victory in December by winning towns across northern England, told lawmakers on Tuesday he would restore discipline to Europe's largest infrastructure project after its costs spiralled.
"The cabinet has given high speed rail the green signal," he told Parliament.
"We are going to get this done, and to ensure we do so without further blow outs on either costs or schedule, we are taking decisive action to restore discipline to the programme."
A review was carried out last year into whether HS2 should go ahead at all, after its predicted cost rose to a reported 106 billion pounds ($137 billion), almost double the bill five years ago.
Johnson said he was backing HS2 as part of a wider revamp of Britain's transport infrastructure, including upgrades to buses and cycle lanes, emphasising a plan to build integrated connections between the regions of northern England.
That fits with Johnson's priority to "level up" the country by investing in transport links outside of London.
HS2, which was initially given government approval in 2012 before questions about its future started being asked last year, will connect London to Birmingham in central England, known as phase one, before splitting into two and going to Manchester in the west, and Leeds to the east.
The government has already spent 7.4 billion pounds on HS2 without laying down any tracks. Physical work has started, however, with buildings demolished, land cleared and utilities rerouted.
Opponents of HS2 have said it would be cheaper and faster to spend money on boosting existing services on conventional lines, but backers of HS2 say the existing track, much of which was built in the Victorian era, is already full and upgrades will not deliver enough new capacity.
($1 = 0.7744 pounds) (Reporting by Sarah Young, additional reporting by Paul Sandle Editing by Kate Holton)