A Free Syrian Army fighter inspects a dead ISIS fighter after they took control of the area in the northern Aleppo countryside, Syria, January 18, 2016.

The Syrian opposition blamed those responsible for the “bombardment and starvation of civilians” for delaying peace talks the United Nations aims to convene on Friday.

The opposition High Negotiation Committee has written to U.N. Secretary of General Ban Ki-moon asking the Security Council to implement a resolution that outlined steps including a halt to bombardment of civilian areas and the lifting of blockades on besieged areas.

“We are serious about taking part (in negotiations), and to start the negotiations, but what is hindering the start of negotiations is the one who is bombing civilians and starving them,” the statement issued by a spokesman for the HNC said.

The Syrian opposition has said it wants such steps implemented before the start of negotiations, which the United Nations aims to convene on Friday in Geneva in an indirect format. The opposition has yet to say whether it will attend.

The source, familiar with an opposition meeting in Riyadh, said the U.N. special envoy for Syria Staffan de Mistura had answered the opposition saying implementation of the resolution was “beyond his authority” and that they were now awaiting a response from Ban.

The source declined to be identified because he is not a spokesman for the High Negotiations Committee.

The demands are also points set out in a U.N. Security Council resolution passed last month.

Meanwhile, the Syrian Democratic Council co-leader Haytham Manna said he has sent the U.N. a list of 15 “essential” names who must be included in Geneva peace talks.

Iran: ‘terrorists in new mask’

Iran said on Thursday it strongly opposed allowing “terrorists in a new mask” to sit down for talks between the Syrian government and the opposition.

“Terrorists with a new mask should not sit down at a negotiating table with the representatives of the Syrian authorities,” Deputy Iranian Foreign Minister Hossein Amirabdollahian told a news conference during a visit to Russia.

“This is the most important condition.”

The Syrian government, aided by Russian air strikes and allied militia including Iranian forces, is gaining ground against rebels in western Syria, this week capturing the town of Sheikh Maskin near the Jordanian border.

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