Russia’s timeline of not delivering airstrikes against groups in Syria that have not joined the cessation of hostilities will run out this week, Russian Foreign Minister Sergei Lavrov said Tuesday.

A US-Russia-brokered ceasefire came into force across Syria on February 27, but it does not apply to terrorist groups such as al-Nusra Front and Daesh.

Earlier in May, Moscow proposed to Washington to conduct joint airstrikes against al-Nusra Front and other terrorist groups refusing to respect ceasefire in Syria. Washington has so far rejected Moscow’s proposal.

“[The United States] has asked us for a few more days before our schedule comes into force, which means those who have not joined the ceasefire will become a legitimate target regardless of the fact if they are in a terrorist list or not. They asked for a few more days in order to react. Those few more days run out this week,” Lavrov said during a live linkup on kp.ru.

The Russian military forces remaining in Syria after a partial withdraw are sufficient to counter terrorist threats remaining in the country, Lavrov said.

“As President [Vladimir Putin] said a couple of months ago, the main tasks of stopping the collapse of the [Syrian] government that was leading to the capture of Damascus, were almost accomplished, we decreased our presence in Syria. Trust me, there are enough forces and equipment there [in Syria] to destroy the remaining terrorist threats.”

Russia has conducted an aerial campaign in Syria since September 2015 after the official request by the country’s president, Bashar Assad. On March 14, 2016, Russian President Vladimir Putin ordered to withdraw most of the country’s military aviation after accomplishing its objective in the fight against terrorism.