Anti-government protesters reinforced their siege of Bangkok's two airports yesterday as the politically paralysed country struggled with 300,000 stranded travellers.

Some of the Britons were able to return home, but thousands of tourists remain stranded.

Foreign Office minister Bill Rammell yesterday said that major airlines including Qantas and Emirates were laying on extra flights with UK Government support to help people stranded in Thailand get home.

An Emirates flight leaving Chiang Mai yesterday evening will have well in excess of 100 British nationals on board, he said.

In a statement released by the Foreign Office, Mr Rammell said: "We are continuing to work with our international partners to support efforts to defuse the unrest in Thailand.

"Several thousand British travellers remain stranded in Bangkok. Our priorities are to ensure their immediate welfare and to find ways of ending their uncertainty and helping them get home.

Thai Airways and Dubai-based carrier Emirates were among airlines laying on extra flights from airports not affected by the protests that have rocked the country in recent days.

Aircraft stuck at the main Bangkok airport were allowed to leave, but some were pulling away empty.

The protesters - members of the People's Alliance for Democracy - stressed they would not allow airports to re-open until the government stood down.

Package tours to Thailand have been suspended, as have British Airways daily services between London and Bangkok.

A spokesman for the Foreign Office said: "The situation in Thailand remains tense and we are following events very closely.

"Bangkok's two main airports remain closed but airlines have been able to arrange flights and transfers to and from alternative airports. Some British nationals have been able to fly out, but not in the necessary numbers."

He added that British Embassy staff were regularly visiting British nationals stuck in Bangkok and providing consular help, such as refreshing supplies of prescription medication.

One of the stranded Britons, advertising agency worker Nadine Howard, from Hampstead in north-west London, is stuck in Phuket.

On a two-week trip with her boyfriend, Ms Howard, who is in her 30s, cannot get a flight from Phuket to Bangkok to get a connecting flight back to the UK.

Her father, Philip Howard, said: "Nadine is distraught and can get no information from her airline (Taiwan-based) EVA Air.

"She's been quoted a figure of £1900 to be flown home from Phuket with another airline, but that's way too high. She feels completely abandoned and is in tears."

Later, EVA Air said it hoped to operate flights from Utapao to London over the next week. Its first service from Utapao arrived in London on Sunday with 300 passengers aboard.

Later, Abta spokesman Sean Tipton said all UK tourists on package holidays in Thailand - about 400 to 500 - should be flown out of the country "by Wednesday or Thursday".

He added that the vast majority of UK tourists stranded in Thailand were independent travellers, including backpackers, who would have to liaise with the Foreign Office and airlines to secure a flight home.

Mr Tipton said: "They should contact the Foreign Office and airlines."

The airport seizure has severed all commercial flights in and out of the capital. Airlines, meanwhile, were flying dozens of empty planes out of Bangkok's Suvarnabhumi international airport.

Meanwhile, the People's Alliance for Democracy told its members occupying the Prime Minister's office compound for the past three months to leave and join compatriots at the airports, which they seized last week in their push to oust the government.

Following the call, the number swelled to about 6000 people at the two airports.

Neither the army nor Thailand's revered king has stepped in to resolve the crisis - or offered the firm backing that Prime Minister Somchai Wongsawat needs to resolve the leadership vacuum.