Russian Foreign Minister Sergey Lavrov has discussed the US missile strike in Syria with US Secretary of State Rex Tillerson in a phone conversation, the ministry has said.

Lavrov told his US counterpart that Washington’s claims, accusing the Syrian army of the use of chemical weapons in Idlib on April 4, were “inaccurate and inconclusive,” the ministry said.

A thorough and impartial investigation must be launched following the alleged chemical attack in Idlib, which the US cited as the reason for its missile strike, Lavrov told the American official.

The US attack ordered by President Trump only played into terrorists’ hands, Russia’s top diplomat told Tillerson.

The call was initiated by the US side, Russia’s Foreign Ministry said. Following their conversation over the phone, the two officials agreed to continue the discussion of the Syrian issue during their planned face-to-face meeting.

The US Secretary of State is set to travel to Moscow next week and hold meetings with a number of Russian officials, including Lavrov.

Earlier Saturday, British Foreign Secretary Boris Johnson canceled his planned trip to Moscow. Citing the recent events in Syria, the UK official pulled out of the Russia trip just hours before he was supposed to depart. Russia’s Foreign Ministry spokeswoman has described the cancellation as “absurd.”