Geneva: The Syrian opposition’s chief negotiator in peace talks in Geneva said on Wednesday he was ‘not optimistic’ about strained efforts to end the nearly five-year war ravaging his country.

Mohammed Alloush, a leading member of the powerful Army of Islam rebel group, told journalists that those pressing to form a unity government with regime members were ‘delusional.’

‘Whoever wants us to go into a unity government with these thugs who kill children is delusional,’ he said, minutes before heading into a meeting with the main opposition grouping, the High Negotiations Committee (HNC).

The HNC was in internal talks on Wednesday morning to discuss its next steps, after a similar, tense meeting the previous evening, an opposition source said.

Asked what the grouping would discuss today, Alloush clutched a picture of a young boy who he said had been severely wounded by Russian air strikes in Syria.

‘The problem is not with (UN envoy Staffan) de Mistura. The problem is with the criminal regime that decimates children and with Russia which always tries to stand alongside criminals,’ Alloush said.

‘A political solution is very important for the HNC, but it is not more valuable than the blood of the Syrian people,’ he said in a statement published by the HNC.

In the statement, Alloush accused the Syrian government of ‘undermining opportunities to reach the negotiations phase by refusing to execute the humanitarian conditions.’

His appointment as chief negotiator has been controversial. Syria’s government and Russia regularly refer to the Army of Islam as ‘terrorists.’

Alloush, a stocky, bearded man in his 40s, also said Kurdish forces fighting jihadists in northeast Syria were ‘a branch of the regime.’

He told reporters the HNC would be taking a decision ‘in two days’ but did not specify what that decision was.

HNC head and former Syrian prime minister Riad Hijab is set to arrive in Switzerland on Wednesday, an HNC spokesman said, in a potential sign of fresh momentum after talks faltered on Tuesday.

The UN-brokered talks in the Swiss city are aimed at ending Syria’s war, which has killed more than 260,000 people.