ANKARA (AFP) Turkish Prime Minister Recep Tayyip Erdogan Monday celebrated a spectacular victory in a referendum on constitutional changes that analysts said strengthened his Islamist-rooted partys chances of winning a third straight term in elections next year. Unofficial results showed that some 58pc of the voters backed the amendments with 42pc against, giving Erdogans Justice and Development Party (AKP) a better-than-expected margin of victory. Turnout was about 77pc. The result...indicates that the AKP remains the dominant party, in EU-candidate Turkey, said Wolgango Piccoli, an analyst with the risk consultancy group Eurasia in a note to investors. The comfortable margin of the yes vote is market positive as it indicates that the AKP has good prospects of winning a third term at the general elections due by July 2011, he added. The result sent the Istanbul stock exchange rallying by 1,297 points on opening to hit an all-time record high of 61,905 points on increased prospects of continuing political stability under a fresh AKP government after the 2011 elections. The AKP, which has its roots in a banned Islamist movement, shot to power in 2002 as an untested party, ending more than a decade of bickering coalition governments, and has since reigned over strong economic growth and introduced a raft of reforms designed to bring the country closer to the Europen Union. But the party is also suspected by many of harbouring a hidden Islamist agenda and has frequently clashed with the military and the judiciary which see themselves as defenders of the countrys strict secular system. The constitutional amendments approved in Sundays vote were aimed at restructuring the countrys top courts and curbing the militarys influence, steps that opponents fear mask an AKP drive to tighten its grip on power and gain a free hand to raise the profile of Islam in the country. The AKP, which denies the allegations, argues that the changes to the constitution, the legacy of the 1980 military coup, would raise democratic standards and draw Turkey closer to its goal of EU membership. In his victory speech Sunday night, Erdogan welcomed the referendum outcome as a turning point for Turkish democracy and announced that he would start work on a brand new constitution after next years elections. However, in a reconciliatory message, he also embraced the no voters and pledged to seek compromise with the opposition for further constitutional reforms. Erdogan must now show that he is sincere in his promise to take the substantial no votes into account and alleviate concerns over the future of the country, political analyst Gungor Mengi wrote in the popular Vatan daily. The most important guarantee that should be given is that the governing party will use its increasing power to put into practice a contemporary regime based on the supremacy of law, he said. Some analysts warned that Erdogan had attained immeasurable power with the referendum result. Nobody can stand in the way of Erdogan now, Mehmet Yilmaz warned the mass-circulation Hurriyet daily. What Turkey will see now is a series of steps that will turn him into Putin, he said, referring to the Russian prime minister. The AKP introduced constitutional amendments to modify the make-up of the Constitutional Court and the Higher Board of Judges and Prosecutors, which deals with judicial appointments, and the way their members are elected. Top courts have often blocked AKP-sponsored legislation, including a bill that would have abolished a ban on the Islamic headscarf in universities. In 2008, the party also narrowly escaped being banned for undermining secularism.