U.S. President George W Bush blamed jet lag on his hurried and 'unenthusiastic' attitude during his visit to Beijing.

The president made the comment during a press conference which he called at the hotel in which he was staying, after he had met with Chinese President Hu Jintao.

Bush cut the conference short after being pressured by a reporter on his attitude but when he strode towards a double-set of doors and pulled on the handles to make an exit, he found the doors locked.

Earlier in the day Bush had met with President Hu and the two men made a statement afterwards but did not take questions.

At his own press conference the U.S.president bristled when asked by a reporter, 'Respectfully, sir, you know we are always respectful, in your statement this morning with President Hu, you seemed a little off your game, you seemed to hurry through your statement. There was a lack of enthusiasm. Was something bothering you?'

Bush replied, 'Have you ever heard of jet lag? Well, good. That answers your question.'

The reporter responded by asking if he could ask another question. The president replied, 'No you may not,' and strode off.

When he reached the doors and tried to open them the president broke into a laugh. One of his aides then came to his rescue and escorted him to the correct doors where he made a hasty escape.