The Heimlich manoeuvre, a short sharp burst of pressure to the abdomen to clear a blockage in the throat, is just as effective when performed by the person who is choking, experts have found.

Doctors from the Royal Brompton Hospital in London warned that too often people were embarrassed when they started choking and sought privacy, often where nobody could help.

But Dr Nick Hopkinson said he and colleagues had discovered that the Heimlich manoeuvre could be self-administered, either by pressing the abdomen sharply onto a chair, or by delivering a similar thrust with their hand.

Dr Hopkinson said that the technique should be taught in First Aid classes, so that people would know what to do if they were on their own when they started to choke.