Britain's Sports Minister Hugh Robertson has backed the 2013 Virgin London Marathon to go ahead as planned this Sunday (April 21) to send a message that the city "won't be cowered" following the two fatal explosions at the Boston Marathon last night.
At least three people were killed and more than 100 injured by the blasts near the finish line of the race, which is the oldest annual marathon in the world having been run since 1897, in the Massachusetts capital.
There have been some suggestions that the London Marathon should now be abandoned amid fears that there could be a second attack at the event but the Sports Minister has unequivocally backed plans from organisers for the race to go ahead as planned.
"These are a balance of judgements but we are absolutely confident here that we can keep the event safe and secure," said Robertson.
"I think this is one of those incidents where the best way to show solidarity with Boston is to continue and send a very clear message to those responsible.
"The best way for us to react is to push ahead with the marathon on Sunday, to get people on the streets and to celebrate it as we always do in London - and to send a very clear message that we won't be cowered by this sort of behaviour.
"As the Minister responsible on a day-to-day basis at the London 2012 Olympics and Paralympics, we lived through this for the past year.
"I was privileged enough to see the Metropolitan Police, the armed forces, security services and our special forces working on this.
"I saw them close up and that gives you enormous confidence."
At least three people were killed and more than 100 injured by the blasts at the Boston Marathon
London Marathon chief executive Nick Bitel made it clear that security will be of primary importance for his team.
"One can't be complacent when it has happened," Bitel said here at the London Marathon headquarters.
"You need to then review those plans you have in place to see what else may be necessary."
St James' Palace has also confirmed that Prince Harry will still attend the event this year to make the presentations to the winners.
Home Secretary Theresa May has been briefed on the bombings by Scotland Yard Assistant Commissioner Cressida Dick and MI5 chief Sir Jonathan Evans.
There are currently no plans for a meeting of the Government's emergency committee COBRA, but high-level discussions were already planned and will go ahead because of the funeral of former Prime Minister Baroness Margaret Thatcher in London tomorrow.
The London Marathon first took place in 1981 and was completed by more than 37,000 people last year.
The route, which is lined by hundreds of thousands of spectators every year, starts in Blackheath and finishes near Buckingham Palace.
It passes some of the capital's most recognisable landmarks including Tower Bridge, Canary Wharf and Big Ben.
Particular focus this year will be on Britain's double London 2012 Olympic champion Mo Farah, who is set to run half of the marathon before doing the full event in 2014.
He is still scheduled to compete in the event while investigations continue in Boston to find the full facts behind the explosion and who was involved.
United States President Barack Obama has promised that any responsible individuals and groups "will feel the full weight of justice" once the investigations had taken place.
International Association of Athletics Federations (IAAF) President Lamine Diack has also condemned the attacks.
"This ghastly and cowardly attack strikes at the very core of the freest of human activities," said Diack, the most powerful figure in world athletics.
"Whether as a fun runner or elite competitor, road running exemplifies the honestly of basic human movement, strength and resilience.
"What makes this incident so vile and its planning so incomprehensible is that marathons the world over are about selfless acts of human generosity.
"Millions of dollars are raised for charity every year by participants in road races.
"The events themselves are administered by thousands of volunteers who freely give their time to operate everything from baggage trucks to water stations to finish lines.
"The streets are lined with countless millions of spectators who selflessly simply wish to applaud, encourage and embrace the best of human endeavour.
"There can be no excuse, no cause which can justify these explosions in Boston which so sicken us all."