Heathrow, Europe's busiest airport, said it had cut around 130 flights - most operated by IAG'S British Airways - from its schedule today to allow more space between aircraft because of low visibility.

"Many airports have plenty of spare runway capacity so aircraft can be spaced out more during low visibility without causing delays and cancellations. Because Heathrow operates at almost full capacity, there is simply no room to reschedule the delayed flights," a Heathrow spokesman said.

The airport scrapped some 250 flights yesterday and said the decision had helped it operate smoothly.

London's second airport, Gatwick, said it was operating as normal but that delays and some flight cancellations were likely because of adverse weather across Europe.

Smaller Stansted airport said that it was open and operational but that it expected to see some Ryanair flights cancelled during the day.

East Midlands Airport, in central England, said its single runway would remain closed until later on Monday, while City Airport - close to London's financial district - re-opened its one runway after closing it earlier in the morning.