The Metropolitan Police commissioner insists she has confidence in the force's professional standards department amid a corruption investigation.

Cressida Dick called it "a ridiculous proposition" to compare the inquiry by the Independent Office for Police Conduct (IOPC) to a massive investigation in the late 1970s and 1980s called Operation Countryman.

She also objected to the watchdog's use of the word "corruption", saying it is associated with officers taking illegal payments.

Comm Dick said: "The word corruption is very easily said and easily bandied around. Most members of the public, or indeed police officers, when they look back and think about police corruption they have an image of, for example, officers doing the wrong thing because they are perhaps being paid to do the wrong thing.

"What is alleged here is something I take very seriously, we're at the very early stages of an investigation, we will see what the evidence is. But I saw some of the coverage which tended to suggest this was an echo of something like Countryman, and that is a ridiculous proposition as I understand it, looking at what we have.

"I take it very seriously because it's my professional standards department. I have confidence in my professional standards department."

Two officers have been put on restricted duties while the investigation takes place.

Last month the IOPC announced it will be probing claims regarding "potentially conflicted" senior officers in the Metropolitan Police's Directorate of Professional Standards (DPS).

IOPC regional director Jonathan Green said: "I can confirm we have begun an investigation into allegations of serious corruption and malpractice within the Directorate of Professional Standards of the Metropolitan Police.

"The investigation includes alleged interference in, and curtailment of, investigations by potentially conflicted senior officers, failure to investigate allegations of wrongdoing, systemic removal of the restrictions of officers under investigation and racial discrimination.

"As part of this investigation three officers have been served with gross misconduct notices and one of those officers is also under criminal investigation. Assessments on the status of a number of other officers remains ongoing."

Operation Countryman was launched in 1978 into claims that officers had taken bribes from organised crime figures. None from the Met were convicted.

At the same event the commissioner also hit out at middle class cocaine users who worry about issues like the environment and fair trade but believe there's "no harm" in taking the class A drug.