UNITED NATIONS - United Nations (UN) Secretary-General Antonio Guterres is concerned about the safety of about 3 million people in northwest Syria because of a recent step-up of attacks, his spokesman said on Wednesday.

"We are particularly concerned over the safety and protection of some 3 million people in Idlib and the surrounding areas of the northwest of the country, including some 1.6 million internally displaced people," said Stephane Dujarric, spokesman for Guterres.

He said that since April the UN Office of the High Commissioner for Human Rights has verified over 1,000 civilian casualties, hundreds of them children, as a result of hostilities.

The spokesman said that "the humanitarian situation throughout Syria remains dire, with more than 11 million people in need of assistance and over 6 million people displaced."