A leading lawyer has claimed institutional racism is "thriving" in the Metropolitan Police, nearly 25 years on from the murder of Stephen Lawrence.

Imran Khan, who has represented Stephen's mother Baroness Lawrence since a few days after her son's death, said a new documentary series on the murder and its aftermath had left him feeling betrayed by the police.

The racist killing and the botched initial murder investigation led to a public inquiry that in 1999 branded Scotland Yard institutionally racist.

Current Commissioner Cressida Dick insists in the new three-part BBC series that the force has moved on in the past 25 years, but Mr Khan said he now believes officers only paid "lip-service" to progress.

Speaking at a screening of the first part of the series, he said: "We had a number of police officers who I had assumed had moved forward with us, who if they had blinkers on then they finally understood what racism was about, or institutionalised racism was about.

"Having viewed all three programmes I feel betrayed by those officers. I feel now that the sense of progress that I think had been made with police officers understanding racism and institutional racism goes back to simply lip service. I think it's now hidden far better than it was but it exists and it's thriving and I think there's a lot more that we've got to do."

The QC believes the programmes "will reignite the feeling among the black community that the police haven't changed at all."

He went on: "I've got angry all over again because I realise that was an awful process for the family to go through, and it's still happening now. The thing I want amongst all communities is to reignite that anger and to hold the Met in particular to account again.

"Because I think we're being fed a lie that things have changed, it has a little bit but certainly I think at the end of the watching of all three, I think I want to reignite that anger and say we've got to hold the Met, the police and the Government to account over this whole process of institutional racism."

Former detective Clive Driscoll, who led the investigation that saw two of Stephen's killers Gary Dobson and David Norris finally convicted of murder, said the issue of racism in the police will be "an ongoing thing for a very, very long time".

"The police need to focus very, very carefully on making sure that they are open and transparent, and if they do come across any discriminatory behaviour then they should come down on that like a tonne of bricks. Otherwise nobody will ever have any confidence in the system or the police, and that makes policing harder."