Prime Minister Abhisit Vejjajiva has now withdrawn an earlier proposal to hold November elections but that reconciliation remains an option.

Mr Abhisit has threatened tough action before and not followed through, since a failed, crackdown on 10 April, which last 25 people dead.

The red-shirts have again expressed defiance, saying they will not move.

Korbsak Sabhavasu, the prime minister's secretary-general, told the Thai Public Broadcasting Service that the election date set in the peace deal that had appeared feasible at the weekend is now off the tackle.

“The proposed date for election has been called off but we will go forward with our reconciliation plans,” Mr Korbsak said.

With positions are apparently hardening on either side and earlier peace plans falling apart, the military has stressed that they will "not use force at this stage".

The protesters blame the government for the deaths of 19 protesters, one journalist and five soldiers in the April 10 crackdown.

PM Abhisit told reporters the cabinet had decided on May 11 that the security forces needed to "take measures" quickly.

The measures will include cutting off power and water supplies and telephones. The city’s infrastructure including buses, trains and the important waterway transport system would almost certainly disrupted and food supplies to the protesters will be blocked, he said.

Thousands of protesters have been camped out in Bangkok for two months, occupying many major thoroughfares in the centre of the city, resulting in the closing of hundreds of shops and hotels in the area.