Emma Thompson has declared war on sloppy speech. The actress, 51, who has penned a new version of the musical My Fair Lady, told the Radio Times that she had been driven “insane” by people who do not speak properly.

She said: “We have to reinvest, I think, in the idea of articulacy as a form of personal human freedom and power.

“I went to give a talk at my old school and the girls were all doing their ‘likes’ and ‘innits?’ and ‘it ain’ts’, which drives me insane.

“I told them, ‘Just don’t do it. Because it makes you sound stupid and you’re not stupid.’”

She added: “There is the necessity to have two languages – one that you use with your mates and the other that you need in any official capacity. Or you’re going to sound like a knob.”

The Oscar-winning star recently caused controversy when she said that screen icon Audrey Hepburn, who played Eliza Doolittle in the original film version of My Fair Lady, was “not a very good actress”.