The peace vigil and memorial has been organised by the British Pakistani Christian Association (BPCA) and their chairman Wilson Chowdhry says it is a chance for people to come together as a society to stand against hatred.
“This event is an opportunity for ordinary people to pay tribute to the heroism of Pc Keith Palmer. His sacrifice reminds us of the bravery of our National Police Service,” said Wilson.
“We have mourned as a nation, now we should celebrate a life that has come to define all that it means to be a good citizen.
“Extremism threatens our society and it is only by working together and condemning hatred where we can, that we can make this world a better place for all to live.”
The rally begins at 12pm in Downing Street where a number of guests, both religious and non-religious, will speak at the event.
At 2pm a procession led by a bagpiper will lay a wreath before the National Police Memorial in Pall Mall.