The ruling AK or Justice and Development Party - whose roots lie in political Islam - presented its package to parliament this week, arguing reforms were needed to strengthen Turkey's democracy as it bids to join the European Union.

If approved, the reforms would change the way judges are appointed to superior courts, make it harder to ban political parties, and make Turkey's traditionally powerful military answerable to civilian courts.

Critics, fearing AK intends reversing modern Turkey's secular values, say the changes would prevent the judiciary providing checks and balances on government as the superior court benches would be filled with AK nominees.

"It seems that the planned regulations will strengthen anti-democratic articles of the constitution, and strengthen articles contradictory to the independence of judiciary, rather than improve the constitution prepared following the 1980 military coup," Hasan Gerceker, chairman of the Supreme Court of Appeals, told a conference at Ankara University.

Prime Minister Tayyip Erdogan plans to put the reform package to a national referendum if the government fails to get the two-thirds majority in a vote that is likely to take place in parliament later this month.

Political analysts say the moves are part of AK's strategy to break the entrenched dominance of conservative secularists in the establishment, whose strongholds are the judiciary and the military.

The government denies having any Islamist agenda and bridles at descriptions of this being a struggle between Islamists and secularists.

Ministers have told judges to stay out of the political arena, but Gerceker called on parliament and the people to reject the government's reforms.

"I believe that first the parliament, and if not, the noble Turkish society will prevent regulations from being implemented that are totally contrary to the judiciary, democratic state of law and principle of separation of powers," he said in remarks reported by the state-run Anatolian news agency.

Gerceker said the government's motive was to escape the scrutiny of an independent judiciary.

The AK Party is gearing up for an election due by July next year when it hopes to win a third term, having first come to power in 2002 when it won a landslide victory over the secular nationalist parties who have traditionally governed.

Having earned respect for guiding the country out of an economic crisis at the start of the decade, the AK is seeking to shore up some of the support it lost as a result of a deep recession last year caused by the global financial crisis.

Ilter Turan, a professor of political science at Ankara's Bilgi University, saw months of turbulence ahead with opponents accusing AK of undermining Turkey's secularism, and possibly calling on the Constitutional Court to block the reforms.

"Turkish voters will have to brace themselves for a no holds barred battle. That is likely to be followed by a tension-ridden referendum," Turan wrote in an analysis for the German Marshall Fund of the United States, a Washington-based think tank.

Investors' worst fear is a replay of the political crisis seen in 2008 when the state prosecutor tried to have the ruling party banned because of its Islamist ties.