A parliamentary vote to select Thailand’s new prime minister expected on Friday was delayed again after a court put off a decision in a case involving the progressive party that won May's election, adding to growing uncertainty about when a new government can take office. The Constitutional Court on Thursday said it needs more time to deliberate on whether to accept a petition from the state ombudsman on whether it was constitutional for Parliament to bar Move Forward Party leader Pita Limjaroenrat, the surprise election winner, from being nominated as a prime ministerial candidate a second time. The progressive Move Forward Party finished in first place in the May election and assembled an eight-party coalition with 312 seats in the 500-member lower house. But Parliament has struggled to confirm a new prime minister, which requires a majority vote together with the conservative 250-member appointed Senate. Pita’s initial bid last month fell short by more than 50 votes, largely because only 13 senators backed him. He was barred from a second try the following week when Parliament voted that he could not submit his name again. Many senators, who were appointed by a previous military government, said they would not vote for Pita because of his party’s call to reform a law that makes it illegal to defame Thailand’s royal family. Critics say the law, which carries a penalty of up to 15 years in prison, has been abused as a political weapon. The Senate’s members see themselves as guardians of conservative royalist values which hold the monarchy to be sacrosanct. Move Forward, whose agenda appealed greatly to younger voters, also seeks to reduce the influence of the military, which has staged more than a dozen coups since Thailand became a constitutional monarchy in 1932, and big business monopolies. After Pita was barred from a second bid, several complaints were submitted to the state ombudsman asserting that the action violated the constitution. The complainants include private citizens and lawmakers from Pita’s party. When the case was filed to the court last week, Parliament postponed the vote but rescheduled it days later, although the court had yet to make a decision. The court said in a statement Thursday that it will meet again on Aug. 16 to decide whether to accept the petition. If accepted, the court could order the vote to be postponed until it issues a ruling. House Speaker Wan Muhamad Noor Matha said the vote for a prime minister would be delayed pending the court's decision. He said Parliament will still convene on Friday to debate a Move Forward petition seeking an amendment of the military-enacted constitution to eliminate the Senate’s de facto ability to veto a prime minister candidate. Regardless of the court ruling, Pita's chances of being nominated again appear nil. Move Forward faces several legal challenges which its supporters see as dirty tricks deployed by its political opponents to cling to power. One of the cases, which accuses Pita of violating the constitution by running for office while allegedly holding shares in a media company, resulted in him being suspended from Parliament last month while Parliament was debating his second nomination. In the latest major blow, Pheu Thai, the second biggest party in the eight-party coalition, which took over the lead role in forming a government after Move Forward's two attempts, said Wednesday that Move Forward has been excluded because its platform to reform the royal defamation law made it impossible to rally enough support from other parties and the Senate. Chonlanan Srikaew, Pheu Thai's leader, said the party does not support Move Forward’s call to amend the law and will form a coalition with new partners and nominate its candidate, real estate tycoon Srettha Thavisin, as prime minister. Pheu Thai is the latest in a string of parties affiliated with ex-Prime Minister Thaksin Shinawatra, a billionaire populist who was ousted in a 2006 military coup. His daughter has announced that he plans to return on Aug. 10 following years of self-imposed exile to escape a prison term in several criminal cases which he has decried as politically motivated. The party’s plan to unveil its new coalition partners on Thursday was also postponed following the court’s announcement. Read More Ukraine war’s heaviest fight rages in east - follow live Charity boss speaks out over ‘traumatic’ encounter with royal aide Pope Francis urges students in Portugal to fight economic injustice and protect the environment Adidas brings in $437 million from selling Yeezy shoes that will benefit anti-hate groups Israel's Supreme Court hears case against a law protecting Netanyahu from being removed from office