Survivors of the 7/7 bombings and relatives of the 52 who died will join David Cameron and Boris Johnson for memorial events on the 10th anniversary of the atrocity, it has been announced.
Final arrangements are being made to mark the date, a decade since the worst terrorist attack on British soil.
The Mayor of London's office told the Standard details of the memorial events would be released in the coming days as preparations were still under way.
The occasion is made all the more poignant by this week's terror attacks in Sousse, Tunisia, in which 15 Brits were killed when an ISIS militant opened fire at a beach resort - named by the Prime Minister as the worst terrorist strike on British nationals since 7/7 itself.
Suicide bombers Mohammed Sidique Khan, 30, Shehzad Tanweer, 22, Hasib Hussain, 18, and Jermaine Lindsay, 19, detonated bombs on two Circle line Tubes, a Piccadilly line train and a number 30 bus.
Twenty-six people died in the bombing at Russell Square on the Piccadilly line while six died at Edgware Road on the Circle Line and seven died in the Aldgate Circle line bombing.
Thirteen people died in the bus bomb, which was detonated at Tavistock Square.
A fortnight later, another four would-be suicide bombers launched failed attacks on the Tube and a bus, leading to police marksmen shooting dead innocent Brazilian Jean Charles de Menezes.
Lindsay's wife Samantha Lewthwaite later fled the UK, reportedly linking up with the al Qaida-linked Somali Islamic extremist group al-Shabab.
Dubbed the "white widow", she is now one of the world's most wanted women and has been linked in reports to various terror attacks, including a 2011 plot to bomb holiday resorts in Kenya.
Additional reporting by Press Association
