Britons in Thailand are being warned by the Foreign Office to avoid large crowds and demonstrations after a military coup to oust the country's PM.
The streets of Bangkok are said to be calm, despite a military presence
Martial law has been declared following the coup, which took place on Tuesday while Prime Minister Thaksin Shinawatra was at the United Nations in New York.
The FO is urging Britons planning trips to Thailand to monitor the situation but has not advised against travel.
Those already in Bangkok should avoid moving around the city, it says.
And it warns movement around government buildings and in public places may be limited.
The Australian government is strongly advising its citizens to reconsider travelling to Thailand and urging "extreme caution" for those already in the country.
Britons living in Bangkok said it was quiet and calm on the capital's streets as the coup entered its second day.
But with a broadcast news blackout in operation, many are relying on the internet for information.
Wednesday has been declared a public holiday, with schools, banks, and the stock exchange closed.
Barry Osborne, general manager of the British Club Bangkok said: "The streets are very quiet but there is no panic, there are some military around the streets of Silom Sukhumvit but mostly it is centred around the Sanam Luang and Dusit areas of the city."
And Mark Fraser, chairman of the British Chamber of Commerce, said there was a light military presence and it was a "little bit like a Sunday".
British Airways said its service to Bangkok was "operating as normal".
The airline is giving passengers booked on flights on Wednesday the option of postponing their trip or transferring to another destination.
But Simon Calder, travel editor of the Independent newspaper, told BBC News this did not apply to other airlines and that those who cancelled holidays would not be covered by their travel insurance.
He said there were between 10,000 and 30,000 British tourists already in Thailand - about 2,000 of them in Bangkok.
But as many of them were backpackers it was hard to tell exactly how many were in the Thai capital.
He said reports from tourist areas such as Phuket, where most Britons were likely to be staying, indicated that it was "business as usual" with tourists continuing their holidays unperturbed.
The Association of British Travel Agents' head of corporate affairs Keith Betton told BBC News that British flights to Thailand would be diverted to land in neighbouring countries if necessary.
Independent travellers should stay off the streets of Bangkok, he added.
A spokeswoman for travel agent Thomas Cook told BBC News there was "no apparent threat to tourists" and the main holiday resorts remained unaffected.
But the company would continue to monitor the situation carefully.
The coup leaders have declared loyalty to King Bhumibol Adulyadej, and it is unclear whether Mr Thaksin intends to return home.
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