Overseas government representatives will travel to Westminster from the location for Queen Elizabeth II’s funeral.
Shortly after 7.30am, dignitaries began to arrive at the in diplomatic cars with dark windows.
The first vehicle to cross the police cordon was registered to Sudan. Abdel Fattah al-Burhan, Sudan’s military leader, is expected to attend the Queen’s funeral.
A car registered to the German embassy has also been spotted arriving at the security cordon around the hospital.
German President Frank-Walter Steinmeier is understood to be attending the funeral.
Other delegations that arrived include Slovenia, Croatia, Nigeria and Malawi.
The Italian president Sergio Mattarella was among the last to arrive in Chelsea in a chauffeur-driven Maserati with the number plate ITA 1.
A senior Buckingham Palace official said they will be “travelling under collective arrangements” to the Abbey.
HM Queen Elizabeth II: Crowds gather for Queen’s State Funeral
The doors of Westminster Abbey opened at 8am for the 2,000 members of the congregation to begin taking their seats.
At 10.44am, King Charles III will lead his family in marching behind the Queen’s coffin as it is moved from Westminster Hall the short distance to Westminster Abbey for the funeral service .
The service, conducted by the Dean of Westminster, will begin at 11am.
More than 500 heads of state and foreign dignitaries will take part including Joe Biden, the first American President to attend a British State Funeral.
It comes after hundreds of foreign dignitaries arrived on Sunday night for a state reception in the picture gallery and state apartments hosted by the King and Queen Consort.
They included the president of Israel, Isaac Herzog; the King of Jordan, Abdullah II; the first lady of Ukraine, Olena Zelenska; and the European Commission president, Ursula von der Leyen.