Determined to put on a show of “solidarity” for Boston, London Marathon organisers are refusing to cave in to the threat of terrorism and will stage their race on Sunday.

The British capital has long been a top target for terrorists, and these concerns have only intensified ahead of this weekend’s race after Monday’s harrowing scenes at the Boston Marathon, where bombs killed three people and injured many more.

“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,” Robertson told the BBC on Tuesday.

“These are balance of judgments but we are absolutely confident here that we can keep the event safe and secure. 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.”

Security is being scrutinised after the events in Boston, where two bombs exploded near the finish of the marathon.

“The London Marathon fully expects at this stage ... (to) go ahead as planned on Sunday although we are continuing to review security with the Metropolitan Police in the coming days,” Nick Bitel, chief executive of the London Marathon, said on Tuesday in an interview on the race website.

“The London Marathon will be in touch with the runners through their email and they will hear from us on a daily basis in that way. We will try to keep updating our runners throughout this period.”

Mo Farah, Britain’s double Olympic long-distance champion, will be running a half-marathon while the three medallists from the men’s marathon at the London Games are also among the 37,500 entries.

Sunday’s race is one of six in the world marathon series along with Tokyo, Boston, Berlin, Chicago and New York.