A Thai court ruled yesterday that the government's ambitious two trillion baht (HK$480 billion) plan to build high-speed rail and other transport infrastructure was unconstitutional and must be ended. The Constitutional Court's ruling was the latest blow to the government of Prime Minister Yingluck Shinawatra, which has been the target of four months of anti-government protests. The seven-year transport plan was a centrepiece policy of the ruling party, which won a landslide victory in 2011 elections. Yingluck's government is now a caretaker administration after early elections in February were disrupted by protests in Bangkok. The court sided with the opposition Democrat Party, which had launched the legal challenge saying that a law authorising the two trillion baht of borrowing would raise public debt to unacceptably high levels and reduce transparency by bypassing the annual budget process. The party's move came after the Senate last year voted in favour of the bill, which would have allowed the Finance Ministry to borrow the money in Thailand and overseas without recourse to the budget. Yesterday's decision included a unanimous 8-0 ruling that the content of the bill was unconstitutional and a 6-2 ruling that the process of drafting the bill was unconstitutional. It was expected to anger Yingluck's supporters who see the courts as sympathetic to the anti-government movement. Last month, the Civil Court ordered the government not to use force against protesters whose movement has included massive demonstrations and sporadic violence in which 22 have died and hundreds have been injured. Footage has shown the protest movement's guards firing guns at police. Transport Minister Chadchart Sittipunt said he hoped the next government would pursue the projects. "These are not just my projects, they are for the whole country," Chadchart said. "This government has done its best to set up the framework for these projects. Now the next government will have to work it out." The seven-year infrastructure spending plan included building four high-speed rail lines that would connect Bangkok with Chiang Mai in the north, the Laotian border, Thailand's industrialised eastern seaboard and Malaysia. The government had said the projects, to be completed by 2020, would boost Thailand's growth, create jobs and improve investor confidence. Protesters accuse Yingluck of being a proxy for her brother, the former prime minister Thaksin Shinawatra. The country has been wracked by political unrest since 2006, when Thaksin was ousted by a military coup after being accused of corruption and abuse of power.