GENEVA (Reuters) - U.N. officials have notified Russia, Turkey and the United States of the GPS coordinates of 235 schools, hospitals and other civilian sites in the Syrian province of Idlib, in the hope the move will help protect them from being attacked.

FILE PHOTO: A man watches as smoke rises after what activists said was an air strike on Atimah, Idlib province March 8, 2015. REUTERS/Ammar Abdullah/File Photo

“We share these coordinates so there is no doubt that a hospital is a hospital,” Panos Moumtzis, U.N. regional humanitarian coordinator for the Syria crisis, told a briefing.

“We would like to see civilians not targeted, hospitals not bombed, people not displaced.”

An estimated 2.9 million people live in Idlib, the last major stronghold of opposition to President Bashar al-Assad. Syrian government and Russian warplanes began air strikes last week in a possible prelude to a full-scale offensive.

Four hospitals in Hama and Idlib have been hit by air strikes in the past week, constituting “serious attacks” that violate international law, Moumtzis said. “A hospital is a hospital and has to be respected by all on the ground.”

Moumtzis called on all warring sides to ensure that civilians in Idlib were able to move freely in any direction to flee fighting or bombing, and for aid workers to have access to them.

He quoted a Russian official as telling a humanitarian task force meeting in Geneva on Thursday that “every effort to find a peaceful solution to the problem is being made”.

The United Nations is working 24/7 to ensure delivery of shelter, food and other assistance if, as feared, hundreds of thousands of people flee, he said.

“In no way am I saying we are ready. What is important is that we are doing our maximum to ensure a level of readiness,” Moumtzis said. “As humanitarians, while we hope for the best we are preparing for the worst.”

An estimated 38,300 people have fled hostilities in Idlib this month, U.N. figures show. About 4,500 of them have returned to their homes following a slight calming, Moumtzis said, calling it a “barometer”.

At least 33 people have been killed and 67 wounded in aerial and ground-based bombing, according to a partial U.N. toll from Sept. 4-9.

Moumtzis said he was going to Turkey for talks with government officials and to oversee preparations for stepping up cross-border aid deliveries to Idlib, where the U.N. is providing supplies to two million people.