A message from the Pope will be read as the requiem mass is held in London on Tuesday following a private funeral held in Southend a day earlier.
The Prime Minister and the Labour leader are both set to pay their respects to the father-of-five after he was stabbed to death while holding a constituency surgery at Belfairs Methodist Church in Leigh-on-Sea on October 15.
The Archbishop of Westminster, Cardinal Vincent Nichols, will preside and Archbishop Claudio Gugerotti, the Apostolic Nuncio to Great Britain, will deliver a message from Pope Francis.
People lined the streets to pay their respects to the Southend West MP as mourners attended a private ecumenical service at St Mary’s Church in Prittlewell on Monday.
Former Conservative MP Ann Widdecombe, a friend of Sir David’s, read a statement on behalf of the Amess family, similar to the one released shortly after his death, asking people to “set aside hatred” and urging tolerance.
Sir David’s coffin, draped in a union flag, was carried by pallbearers from Southend Fire Service.
After the church service, they carried the coffin to a horse-drawn hearse for a procession around Southend.
Hundreds of people gathered outside Southend’s Civic Centre to pay their respects as the hearse, led by four black horses, paused in front of it.
Uniformed police officers bowed their heads as the hearse arrived and people applauded.
Southend West MP Sir David was killed during a constituency surgery in Leigh-on-Sea in Essex on October 15.
Ali Harbi Ali, 25, has been charged with his murder and also with preparing acts of terrorism between May 1 2019 and September 28 this year.
He is due to enter pleas in December.
Following his death, MPs paid tribute to Sir David in the Commons and a service was held in Sir David’s honour at St Margaret’s Church.
Prime Minister Boris Johnson and Labour leader Sir Keir Starmer were among around 800 politicians in attendance to hear the Archbishop of Canterbury say the “light lit by public service” provided by MPs like Sir David “must never be put out”.