Travellers from London airports faced further delays a day after fog grounded 140 flights and left more than 1,000 people stranded overnight at Heathrow.

The airport has cancelled 64 flights as a knock-on from Sunday's problems but said the situation would improve later because the fog had already lifted.

If ever there was a good case for expanding Heathrow, this is it. There simply is not enough slack to cope with problems such as low visibility.