Boris Johnson received boos from sections of the crowd as he walked up the steps of St Paul’s Cathedral with his wife Carrie for the National Service of Thanksgiving for the Queen’s Platinum Jubilee.
The Prime Minister and his wife were met by jeers although there were also cheers from some spectators.
The pair have since taken their seats in the cathedral.
It comes as speculation mounts that Mr Johnson could face a no confidence vote as early as next week following the fallout from Partygate.
A report by ethics chief Lord Geidt said his Partygate fine may have broken the ministerial code and demanded he explain himself.
Labour deputy leader Angela Rayner said Mr Johnson was trying to "rig the rules".
Around 30 backbenchers have publicly called for the prime minister to resign, and speculation is mounting that they are close to reaching the threshold of 54 no-confidence letters needed for a leadership ballot.
High-profile politicians including Sadiq Khan, Keir Starmer and Priti Patel have also been spotted entering the cathedral.
Meanwhile, the Queen will miss today’s thanksgiving service "with great reluctance" after experiencing "some discomfort" during celebrations on Thursday.
Buckingham Palace said: "Taking into account the journey and activity required to participate in [the] National Service of Thanksgiving at St Paul’s Cathedral, Her Majesty with great reluctance has concluded that she will not attend."
Prince Andrew will also miss the service after testing positive for Covid-19. It was the only official jubilee event he had been due to attend.
The prince’s last public appearance was at a memorial service for the Duke of Edinburgh in March.
