Erdoğan says Turkey will never kneel down to any threat

The Turkish nation will resist any threats, Turkish President Recep Tayyip Erdoğan said speaking at a conference after the launching of a military operation into Syria on Wednesday.

"The attacks that targeted our country from Syria have come to such a level that leaves us no choice but to solve this problem immediately and the process for this started today," Erdoğan said.

Turkey launched a cross-border operation in Syria against the DAESH terrorist organisation at 01:000 GMT on Wednesday. The operation comes in response to terrorist attacks on Turkish soil and artillery fire by DAESH on Turkish border towns.

The operation, called Euphrates Shield, is in line with the country's rights to self-defence borne out of international treaties and a mandate given to the Armed Forces by the Turkish parliament in 2014 that was extended for another year in September 2015, Turkish officials said.

Since January, rocket attacks on the Turkish province of Kilis from DAESH-held territory in Syria have killed at least 21 people while a suicide bombing on Saturday in Gaziantep which was blamed on DAESH killed 54 people.

Erdoğan says world must unite against terrorism

"If the world does not reach an agreement against on terrorism then everyone is responsible for the consequences," Erdoğan said after the operations were launched. "So a unified fight is a must."

"DAESH has nothing to do with Islam. On the contrary, it is the biggest trouble for Islam in this century," the president added.

Turkey, which shares a long border with Syria, is a member of the US led-coalition against DAESH in order to find a political solution to the Syrian conflict.

Meanwhile, US Vice President Joe Biden visited Turkey's capital Ankara on Wednesday for a planned meeting with Turkish Prime Minister Binali Yıldırım as well as with President Erdoğan.

Turkey's operation in Syria ahead of a ground offensive by Ankara-backed opposition fighters against DAESH will be among the topics discussed.