Chidchai, who is acting as prime minister following Thaksin Shinawatra's decision to step aside, said he had only commented that the mega-projects should not be delayed for a long time and insisted the matter will be considered by the new government and not under his brief tenure.

"I simply put forward my view after comments from various parties that the new government should not pursue mega-projects. I think they should continue because we can't wait on issues like traffic congestion. Those who speak [against them] should be reasonable," Chidchai said.

He also denied saying that many countries that had been interested in becoming partners on mega-projects are now delaying their investment plans.

Chidchai said the caretaker government would only make decisions on matters that will not be binding to the incoming government.

Democrat Party secretary-general Suthep Thuagsuban warned yesterday, however, that the national interest should be the primary concern of any mega-projects as many have criticised the proposed deals as being equivalent to giving national concessions to foreign firms.

"The government must be careful. It must clearly explain its aims to the people and that can't be done in a short period of time. The important point is that the contracting of these projects must be done transparently and with a certain [minimum] standard.

"These projects will affect Thailand in the long run and we'll have to pay back any borrowed funds. It's also important to make sure no particular person [unlawfully] benefits from the deals," said Suthep.

He said the government should first be certain that each mega-project is truly necessary.

The Thai Rak Thai Party was not against the construction of further mass-transit projects if they were deemed necessary, Suthep said.