Turkish President Recep Tayyip Erdogan says he has responded positively to a U.S. request for a joint operation against Islamic State’s self-declared capital in Syria, Hurriyet newspaper reported.

Erdogan, speaking on his plane following a visit to China, said President Barack Obama personally asked for joint action against the militants’ Raqqa stronghold, 100 kilometers (60 miles) south of the Turkish border, Hurriyet and other newspapers reported. Erdogan said he told Obama “it would not be a problem for us,” media quoted him as saying.

“Our soldiers should get together and whatever needs to be done can be done,” Erdogan said, adding that Turkey and U.S. have been working in harmony so far in the operation against Islamic State.

Turkish hesitation would allow Islamic State and Kurdish “terrorist organizations” to settle there, Erdogan said. “From now on, we have to demonstrate our presence in the region,” he said.

A Turkish offensive has already pushed the militant group from the border town of Jarablus and Turkish tanks and armored units are advancing toward the Islamic State-controlled town of al-Bab, northwest of Aleppo.

The incursion began on Aug. 24, days after a suicide bomber said to be linked to Islamic State killed at least 54 people at a wedding in the border city of Gaziantep. The operation is also meant to deter further advances by Syrian Kurds allied with Turkish separatists.

An Islamic State rocket attack on a Turkish tank north of al-Bab killed 3 Turkish soldiers and wounded four others in Syria on Tuesday, the military said.