New York dead will also be honoured on Sunday

War on Terrorism: Remembrance Sunday

The victims of the 11 September atrocities will be commemorated in special Remembrance Sunday ceremonies tomorrow as the Government seeks to reinforce public support for military action in Afghanistan.

In what the Royal British Legion said could be an annual event, those killed in the attacks on New York and Washington will be honoured as well as those lost in the two world wars.

To underscore the links between the US and Britain, William Farish, the American ambassador, will become the first non-Commonwealth representative at the Cenotaph ceremony in London.

Jack Straw, the Foreign Secretary, will also attend a remembrance ceremony in New York which will include representatives from all the nations who lost citizens in the attacks.

The Cenotaph decision was revealed by Downing Street as it claimed Osama bin Laden was "losing" the propaganda war. In an attempt to maintain the momentum against the leader of al-Qa'ida, the Government announced it would publish next week an updated dossier of evidence implicating him in the events of 11 September.

The Royal British Legion said the decision to remember the victims of 11 September alongside the war dead followed spontaneous gestures of remembrance from the public in the past week.

Of the 15,000 crosses in the Legion's Field of Remembrance in St Margaret's Church in Westminster, a "substantial number" have had the words "New York, Washington, 11 Sept ember" added by the public.

An annual official recognition of the 11 September victims at the Cenotaph was "very much in the realms of possibility", the Legion's spokesman said.

"This year, there will be an added poignancy as we remember not only those who died in the service of their country in the First and Second World Wars and in more than 70 conflicts since 1945, but also those who lost their lives as a result of terrorism," he said. "With our armed forces once again facing active service, this time in Afghanistan ... people are wearing their poppies with extra pride."

Alastair Campbell, Tony Blair's communications director, said Remembrance Sunday was "a fitting time to explain why we are engaged" in Afghanistan. "We see this as an important moment and time to remember why we are engaged in the cause against bin Laden and al-Qa'ida and those who shelter them."

Tomorrow is the first time since 1990 that Armistice Day, marking the end of the First World War, has fallen on Remembrance Sunday.