Turkey launched an assault on Kurdish forces in northern Syria yesterday with air strikes and artillery fire reported along the border.

President Recep Tayyip Erdogan announced the start of the attack on Twitter, labelling it “Operation Peace Spring”. Erdogan said the operation would target both Kurdish militants and IS. “Our mission is to prevent the creation of a terror corridor across our southern border, and to bring peace to the area,” he wrote on Twitter. Ankara says it is necessary to curb the power of the SDF due to its ties with Kurdish insurgents inside Turkey.

World leaders have condemned Turkey for launching the attack. United Nations Secretary-General Antonio Guterres said any military operation must fully respect the U.N. Charter and international humanitarian law. Spokesman Farhan Haq said: “Civilians and civilian infrastructure should be protected. The secretary-general believes that there’s no military solution to the Syrian conflict.”

European Commission President Jean-Claude Juncker urged Turkey to show restraint and stop its military operation. “If the plan involves the creation of a so-called safe zone, don’t expect the EU to pay for any of it,” he said.

NATO chief Jens Stoltenberg said he hoped Turkey’s operations in Syria would be measured and proportionate. Egypt’s foreign ministry condemned the offensive as “a blatant and unacceptable attack on the sovereignty of a brotherly Arab state”. It called for an emergency meeting of the League of Arab States.

German Foreign Minister Heiko Maas said Turkey’s operation would lead to further detribalization of the region and could strengthen Islamic State. He urged Turkey to end the operation. France’s European affairs minister Amelie de Montchalin said France and Britain would call a U.N. Security Council meeting over the Turkish offensive. France, Germany and Britain are finalizing a joint statement condemning the advance.

Italian Prime Minister Giuseppe Conte said the operation risked destabilizing the region and harming civilians. Danish Foreign Minister Jeppe Kofod tweeted: “Deeply concerned about Turkish military operation in Syria. In my view, this is a regrettable and wrong decision, which can have serious consequences for civilians and the fight against ISIL (Islamic State). Turkey must show restraint.

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