Rock band Queen have invited emergency services personnel who dealt with the London bombings to their Hyde Park concert as a gesture of thanks.
Tens of thousands are expected at the concert
Queen frontman Paul Rodgers said he wanted Friday's concert - postponed in the wake of the attacks - to become a tribute to their work.
Guitarist Brian May called them heroes for "getting London's wheels turning again".
The concert is expected to be attended by some 85,000 people.
It was supposed to be held last Friday, but was postponed for a week in light of the London bombings.
Rodgers added: "We feel it is fitting to thank London's emergency services for their extraordinary response in dealing with the effects of the bombing attacks and to celebrate the historical resilience of Londoners in their response to yet another atrocity."
Rodgers, the former singer of the 1970s band Free, has been singing in place of Freddie Mercury, who died in 1991.
Guitarist Brian May said: "We were away playing a concert in Germany and arrived back Thursday morning to see all this going on. We were unbelievably shocked and saddened.
"The heroes that day, and since then, are the police and emergency services coming together as one, calmly and bravely dealing with the tragedy and getting London's wheels turning again. We'd like to offer an appreciation."
It will be the first time Queen have played in Hyde Park in 29 years.
They will be joined by Razorlight, Justin and Dan Hawkins from The Darkness and comedian Peter Kay.