The Metropolitan police in London will challenge the allegation by senior British-Asian officer Tarique Ghaffur, who has accused Scotland Yard of racial discrimination.

Deputy Commissioner of the Metropolitan Police Sir Paul Stephenson, said the force would "robustly challenge" the allegations made by Ghaffur.

"In short, I think it is long past time that we all shut up, stop making public statements about private disputes and get on with the job we are paid to do," said Stephenson, in a statement responding to Ghaffur's allegation.

Senior officers believe they can no longer work closely with 53-year-old Assistant Commissioner who is expected to seek 1 million pounds in compensation if his demands – which include an apology and contract extension to regain full control of security for the 2012 Olympics - are not met.

Ugandan-born Ghaffur whose parents were from Pakistan, arrived in Britain in the early 1970s said, "My family and I came to this country as refugees to live the dream of a better life. The opportunity that was given to me I took with both hands and for the past 33 years it has been an honour to serve as a police officer in a number of police forces and the Met."

Then he went on the attack, alleging he had been "victim of both race and religious discrimination" and "victimised" since his claim became public.

Ghaffur had earlier claimed Metropolitan Police and Commissioner Sir Ian Blair had discriminated against him "over a long period of time" and sidelined him from his job in charge of security for the 2012 Olympics.