Turkey said on Friday its top four military chiefs were all seeking retirement, in moves that appeared to reflect a deep rift between the secularist military and a government with roots in political Islam.
State-run Anatolian news agency said the head of the armed forces General Isik Kosaner and the commanders of the ground, naval and air forces were all stepping down, in what some Turkish media initially described as resignations.
Kosaner said he was quitting his post in protest at the jailing of military officers in a variety of court cases which meant he could no longer defend the rights of his staff, the Hurriyet news website reported.
"It has become impossible for me to continue in this high office because I am unable to fulfill my responsibility to protect the rights of my personnel as the Chief of General Staff," Kosaner was reported as saying.
The reason for the other generals' move was not immediately clear, but tensions between the military and the government of Prime Minister Tayyip Erdogan have run high in recent years.
Following the retirement, Turkish President Abdullah Gul approved the appointment of General Necdet Ozel as the new commander of Turkey's ground forces, TV channels reported.
Ozel was subsequently expected to be appointed the chief of the General Staff in place of Kosaner. Tradition dictates that only the ground forces chief can take over the armed forces.
The Supreme Military Council is due to hold a major twice-yearly meeting next week dealing with key appointments. Gul and Erdogan met Kosaner on Friday to discuss the matter.
Following the announcement Erdogan met the head of Turkey's gendarmerie paramilitary force, General Necdet Ozel, and they subsequently went separately to the presidential palace to meet President Abdullah Gul, fuelling speculation Ozel may be appointed to replace Kosaner.
By tradition, the head of the ground forces replaces the armed forces chief when he retires.
Friction between the government and military, traditionally guardians of the secular state, has been fueled by the continuing trial of 200 military officers accused of plotting to overthrow the government.
The "Sledgehammer" case, arising from an alleged coup plan presented at an army seminar in 2003, is one of several setting Turkey's secularist establishment against Erdogan's ruling AK party. Critics say AK has a secret Islamist agenda, an allegation it denies.
Some 165 military personnel, including more than 40 generals, are in custody in the coup plot trials, severely damaging the military's operational ability.
Anatolian initially reported Kosaner as resigning "as he saw it as necessary," but subsequently withdrew the story, saying instead that he had sought retirement.
The Turkish lira weakened sharply on the news to 1.6964 against the dollar from an interbank close of 1.6805 on Friday.
The Supreme Military Council (YAS) meeting, set to start on Monday, could now be postponed. A row over appointments emerged ahead of last year's YAS, but was resolved by delaying some appointments and the retirement of some senior officers.
A prosecutor investigating another alleged plot involving military officers on Friday sought the arrest of 22 people including the commander of the Aegean army, media reports said. It was not clear if the generals' move was linked to this.
There was uncertainty in financial markets about what the decision by the generals meant, amid reports that their retirement was looming anyway, but Royal Bank of Scotland economist Timothy Ash said it appeared to be a "symbolic step."
He linked it to the coup plot trials, including those targeting "Ergenekon," an alleged secret network involved in anti-government conspiracies.
"It seems to relate to issue of military promotions stalled by legal action around Ergenekon," Ash said.
"Hard to see the military winning this battle, given the ruling AK Party got 50 per cent poll support in the June elections, and now dominates institutions of state," he added.
The Turkish armed forces carried out three coups between 1960 and 1980 and pressured the country's first Islamist-led government out of power in 1997.
Such intervention is no longer regarded as feasible, as the power of the military has been curbed sharply under reforms carried out by Erdogan's government with the aim of winning European Union membership.
Kosaner, who took over as head of the armed forces in August 2010, is regarded as a hardline secularist, but he has kept a lower profile than previous chiefs of the general staff.
Alongside Kosaner, the land forces head Erdal Ceylanoglu, air forces chief Hasan Aksay and navy commander Ugur Yigit have also sought retirement, the reports said.
The announcement comes amid an upsurge in violence in southeast Turkey in the military's battle against separatist Kurdistan Workers Party (PKK) guerrillas.
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