Downing Street said David Cameron was ready to "listen to the arguments" about a ban on smoking in cars that are carrying children.
The Prime Minister's official spokesman told a media briefing, "This is an issue that is going to be discussed and debated in Parliament today, and the Prime Minister's view is that he wants to listen to the arguments."
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In an embarrassing setback for the president, Republicans failed to reach the number of votes to pass his new healthcare act into law.
It will feel pleasantly warm in the sunshine, with temperatures reaching 12 or 13 Celsius (54 to 55F).
Some of Britain's biggest stars of the stage and screen will be honoured at Buckingham Palace later today.