Turkey detained 10 retired admirals who signed a statement asserting the importance to Turkish security of the Montreux Convention designed to prevent the militarization of the Black Sea.
The statement, signed by 104 former admirals, drew a backlash from officials who saw it as a direct challenge from the military to the civilian government. Various ruling Justice and Development Party (AKP) officials accused the former soldiers of suggesting a coup.
Ergun Mengi, Atilla Kezek, Alaettin Sevim, Ramazan Cem Gürdeniz, Nadir Hakan Eraydın, Bülent Olcay, Kadir Sağdıç, Türker Ertürk, Turgay Erdağ and Ali Sadi Ünsal were detained as part of the investigation that was launched into the admirals over "conspiring against state security and constitutional order." Engin Baykal, Cemil Şükrü Bozoğlu, Mustafa Özbey and Atilla Kıyat were called to report to police within three days.
"The fact that withdrawing from the Montreux Convention was opened to debate as part of talks on Kanal Istanbul and the authority to exit from international treaties was met with concern," the admirals said in their declaration.
Kanal Istanbul, an artificial canal project that aims to connect the Black Sea north of Istanbul to the Marmara Sea to the south, has been President Recep Tayyip Erdoğan's "crazy project." The AKP says it will ease shipping traffic on the Bosphorus Strait, one of the world's busiest maritime passages, and prevent accidents.
The controversial project has triggered a debate on the revision of the 1936 Montreux Convention, with 126 retired Turkish envoys releasing a statement on April 1 to warn the government.
“Kanal Istanbul will open the Montreux Convention to discussion and will lead to Turkey’s loss of absolute sovereignty over the Sea of Marmara,” the statement read.
The former diplomats' statement came after Parliament Speaker Mustafa Şentop's remarks on Erdoğan having the authority to withdraw from the Montreux Convention.
"He can say 'I quit the convention.' But there is a difference between possibility and probability," Şentop said on March 24.
Şentop was responding to a question about Erdoğan's authorities on international treaties since the Turkish president withdrew from the Istanbul Convention - an international accord designed to protect women - with a midnight decree on March 20.
The Montreux Convention governs the use of the Bosphorus and Dardanelles straits by cargo ships from other countries. It gives Turkey control over the straits within its borders, and during peacetime guarantees access for civilian vessels. It also limits access of naval warships.
"Montreux provided Turkey the possibility to maintain its neutrality during World War II. We are of the opinion that there is a need to avoid any statements and actions that could cause the Montreux convention, an important treaty in terms of Turkey's survival, to be brought up for discussion," the statement by retired military officials said.
CHP: This is a shameful day for Turkey
The main opposition Republican People's Party (CHP) slammed the detentions, with deputy Engin Özkoç saying that the day is a shameful one for Turkey.
"Retired admiral Cem Gürdeniz was detained from his home. This is a shameful day for Turkey. We've seen these games being played before," Özkoç said on Twitter on April 5.
"Patriots won't bow down just like they didn't in the past," he added.