Thousands of Britons remain stranded in Thailand as the Foreign Office has vowed to "step up" efforts to repatriate them.

They have been caught in the impasse between protesters and the Government as demonstrators entered their seventh day of occupation of Bangkok's main airports.

Greater numbers of people were now being bussed to airports outside of the capital in a bid to fly them back to the UK, it has been claimed.

But Foreign Office minister Bill Rammell appeared to rule out using government-chartered flights, saying that they would not help people get home any quicker.

Mr Rammell said: "The key issue is the fact the two airports in Bangkok are closed and therefore you've effectively got planes stacking up and not being able to get slots."

The Government has urged Thai authorities, the army and protesters to work together to resolve the crisis quickly.

Demonstrators, members of the People's Alliance for Democracy (PAD), accuse the Government of being a puppet of ousted former premier Thaksin Shinawatra.

They occupied Bangkok's Suvarnabhumi international airport on Tuesday as part of a campaign to force current prime minister Somchai Wongsawat from office. The following day they seized Don Muang airport.

Thai media suggests that as many as 100,000 tourists have been stranded as a result of the protest.

And the situation appeared to deteriorate over the weekend with reports of a series of explosions injuring dozens of protesters.

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

"We regret the violence surrounding the protests and have reiterated to the government, the army, the demonstrators, and others in Bangkok, that all parties need to work to resolve the crisis, respecting the rule of law and the country's democratic institutions.

"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.

Meanwhile, the anti-government protest movement is preparing to return Government House, which it has occupied since August, to the authorities.

Suriyasai Katasila, a leader of PAD, said that government officials and independent observers would be invited to inspect the occupied compound on Tuesday and it could be handed over later that day.

"If everybody is happy, we may hold a returning ceremony tomorrow," he said.

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