ANKARA: US Secretary of State John Kerry arrived in Ankara Friday for talks aimed at building a coalition against Islamic State, a visit that comes after Turkey said it would not allow its air bases to be used for strikes on the extremists.

The top US diplomat, touring the Middle East to establish a coalition of more than 40 countries, is to meet with Turkey’s leaders including President Recep Tayyip Erdogan for talks on measures to defeat the militants in Iraq and Syria.

Turkey, a NATO member and Washington’s key ally in the region, is reluctant to take part in combat operations against Islamic State militants, or allow a US-led coalition to attack terrorists from its territory.

On arriving in Ankara, Kerry said that the US would provide an additional $500 million humanitarian aid to victims of the war in Syria, bringing total American assistance to $2.9 billion since the start of the conflict in 2011.

“This is the largest funding announcement made by the United States in response to the largest appeal the United Nations has ever issued,” a statement said.

The German government will not take part in airstrikes, an aide to Chancellor Angela Merkel said on Friday. “The stabilization of the region is of great concern to the German government but I can rule out participation in military air strikes,” said Merkel’s spokeswoman Christiane Wirtz.

Germany said it had prohibited activities in support of the IS, warning the “terrorist” group also posed a threat in Europe.

Interior Minister Thomas de Maiziere said the immediate ban included the recruitment of fighters, the public display of the IS symbols and signs and social media propaganda. “Germany is a well-fortified democracy, there’s no place here for a terrorist organization which opposes the constitutional order as well as the notion of international understanding,” he said in a statement.