Newly-elected Labour leader Jeremy Corbyn has arrived for his first official engagement at the Battle of Britain memorial service at St Paul's Cathedral.
He was wearing a tie and was accompanied by his deputy Tom Watson.
There had been suggestions Mr Corbyn wasn't keen to attend but it seems such concerns were unfounded.
In a statement released to mark the ceremony, Mr Corbyn praised those who had helped Britain and the allies defeat the Nazis.
My mum served as an air raid warden and my dad in the Home Guard.
Like that whole generation, they showed tremendous courage and determination to defeat fascism. The heroism of the Royal Air Force in the Battle of Britain is something to which we all owe an enormous debt of gratitude.
The loss of life - both civilian and military - should be commemorated so that we both honour their lives and do all that we can to ensure future generations are spared the horrors of war.
Veterans and current RAF personnel have arrived at St Paul's Cathedral ahead of a service commemorating the 75th anniversary of the Battle of Britain.
One of those outside the famous London landmark ahead of today's ceremony was 94-year-old Eileen Younghusband, who helped track aircraft during the three-and-a-half month battle.
Younghusband was 18 when she joined the Women's Auxiliary Air Force, and detected the first of Hitler's V2 rockets as they fell on London.
Another veteran, former Hurricane pilot William Clark, was presented with the Africa Star outside the cathedral as he celebrated turning 95.
The service will be followed by an aerial display at Goodwood in Sussex, during which Prince Harry will fly a Spitfire to mark the anniversary.
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