Sir Patrick Vallance, the chief scientific adviser, said that the risks of travelling on holiday or for business are no greater than staying in the UK as soon as Covid-19 becomes widespread.

"Once the epidemic is everywhere, then actually restricting travel makes no difference at all," he said. "At the moment we are certainly not recommending any change to behaviours in relation to that. If it grows in the UK, then of course it doesn't really make more sense to say that you're at more risk somewhere else than you are here."

Professor Chris Whitty, the chief medical officer for England, advised people against travel to countries with a weaker health system than the NHS and suggested they choose a location based on the quality of treatment that would be available.

"If you happen to be in a place with a very weak health service at the peak of their epidemic, weaker than the NHS, that obviously might be more problematic – and this is particularly an issue for people who are older or have pre-existing health conditions," Prof Whitty said.

The Coronavirus action plan says Foreign Office travel advice provides the necessary information "for British nationals ... on what they need to know before deciding whether to travel and what to do if they are affected by an outbreak of Covid-19 while travelling".

On Monday, both British Airways and Ryanair announced flight cuts, with BA dropping 432 flights between March 16 and March 28, and Ryanair cutting a quarter of flights to and from Italy between March 17 and April 8.

But at a meeting of airline executives in Brussels on Monday, bosses warned of further economic damage to come. Willie Walsh, the chief executive of British Airways owner IAG, said there had been "a very significant fall-off in demand" in Europe, especially in Italy, but predicted that it would stabilise in the coming weeks following a pattern seen in Asia.

Emma Wiseman, a spokeswoman for flight comparison website Skyscanner, said a study of the cost of flights to 10 destinations from the UK for both February and June showed prices fluctuating with no obvious link to the virus spread.

But Ms Wiseman warned of rises on routes where flights had been cut, including London to New York – which has seen flights in June rise by an average of 10 per cent. "It's too early to say if recent events are likely to drive any permanent changes to flight pricing," she added.