ANKARA/ISTANBUL - Turkish President Recep Tayyip Erdogan on Wednesday called for a new constitution after his ruling Justice and Development Party's (AKP) weekend triumph at the ballot box.

"Solving the issue of a new constitution was one of the most important messages of November 1," he said in a televised speech in Ankara. Erdogan, the strongman of Turkish politics for more than a decade, has long been pushing for a new constitution to replace a military-drafted charter and expand the powers of the presidency.

Earlier Wednesday, his spokesman said Turkey was considering holding a referendum on changing from a parliamentary to a presidential system. But opponents fear it would put too much power in the hands of a leader they already consider too authoritarian.

Erdogan called on all political parties to work on new civilian constitution that would replace the 1980 charter drafted by the military after a coup. "I hope they will sit down at the table and solve this issue," he said, adding that he had discussed it at a meeting with Prime Minister Ahmet Davutoglu on Tuesday.

Mmoreover, nine alleged members of Islamic State believed to have been preparing a suicide bomb attack on a political party's offices in Istanbul have been remanded in custody by a court in southeast Turkey, the local governor's office said.

Police detained two of the suspects after a brief car chase in the southeastern Turkish city of Gaziantep on Friday and seven more suspects were detained in subsequent police raids, the Gaziantep governor's office said in a statement dated Tuesday.

"The group members were caught with the vehicles, grenades, explosives and weapons they were going to use in the attack. Bloody attacks aimed at creating an atmosphere of fear and chaos before the parliamentary elections were prevented," it said.

In Sunday's election, the ruling AK Party recovered the parliamentary majority which it lost in a vote five months earlier. Turkey has conducted attacks on Islamic State (IS) militants in Syria, and President Tayyip Erdogan had said operations against them and Kurdish militants would continue after the vote.

The Gaziantep governor's office said the suspects were planning the attack on unidentified party's offices in Istanbul on the orders of senior IS members in Syria. Turkish prosecutors last week said there was strong evidence that an IS cell in Gaziantep carried out a spate of bombings culminating in a double suicide attack that killed more than 100 people in Ankara. Turkish warplanes have again struck Kurdish rebel targets in the southeast of the country and northern Iraq, the military said Wednesday.

"Sixteen targets were destroyed as a result of air strikes," the army said after the operations Tuesday that focused on Turkey's mountainous Daglica region near the Iraqi border as well as several regions in northern Iraq. Similar strikes were carried out on Monday against the Kurdistan Workers' Party (PKK), the day after an election that returned the Justice and Development Party (AKP) to power.

Four Kurdish militants died Tuesday after clashes with Turkish security forces in several parts of the restive southeast, security sources said. Also Tuesday, Ankara ruled out any resumption of the peace process with the outlawed PKK after a wave of violence erupted in July, leaving a 2013 ceasefire in tatters. Two Turkish soldiers were killed in fighting with Kurdish rebels in a southeastern town near the Iraqi border on Wednesday, the army said.

"Two hero comrades fell as martyrs during clashes that erupted after an operation" in Yuksekova, the army said on its website, adding that one soldier was also wounded. Violence has flared again between Turkish security forces and members of the outlawed Kurdistan Workers' Party (PKK) since a weekend election that returned President Recep Tayyip Erdogan's party to power.

Erdogan said earlier Wednesday there would be "no break" in the military campaign against what Turkey and the West considers a terrorist group. Turkish warplanes bombed PKK targets in southeastern Turkey and northern Iraq on Monday and Tuesday, the first such action since the election.

Four militants were also been killed in clashes this week with Turkish security forces in the Kurdish-majority southeast. Meanwhile, police detained 22 people on Wednesday in an operation against the youth and urban wings of the PKK in Istanbul and in the southern province of Adana, local media reported. The government said Tuesday that conditions were not yet ripe to resume peace talks with the Kurdish militants which collapsed after a fresh outbreak of violence in July.