LONDON, Dec 10 (Reuters) - London"s Heathrow Airport (FERHT.UL) said it was seeing high levels of business travellers cancelling over concerns they could be trapped overseas by travel restrictions triggered by the new Omicron variant of coronavirus. The airport said demand in November was down 60% on pre-pandemic levels, despite the United States reopening to transatlantic travel earlier in the month. The figures released on Friday show that the start of a gradual recovery seen in October, when demand was down 56%, had petered out. Heathrow CEO John Holland-Kaye called on the British government to reduce restrictions as soon as it was safe to do so, including allowing UK nationals arriving from red list countries to isolate at home. "It would send a strong signal that restrictions on travel will be removed as soon as safely possible to give passengers the confidence to book for 2022, opening up thousands of new jobs for local people at Heathrow," he said. "Let"s reunite families for Christmas."