The UN Security Council has failed on Thursday to agree a joint statement denouncing an air strike on a migrant detention center in Libya where 44 people were killed and more than 130 were seriously injured.

Reports citing diplomats in New York indicate that the United States “was not prepared to support” the text of a proposed statement without approval from Washington.

Libya's UN-backed-government and rebel militias have blamed each other for the attack.

During a two-hour closed-door meeting, Britain circulated a statement that would have condemned the deadly air strike blamed on commander Khalifa Haftar's forces, called for a ceasefire and a return to political talks.

But US diplomats told the meeting that they required a green light from Washington to approve the text and the talks ended without US approval, sources told AFP At least 44 people were killed when the air strike hit the Tajoura detention center late on Tuesday and more than 130 were severely wounded, according to the UN Peru's Ambassador Gustavo Meza-Cuadro, whose country holds the council presidency, told reporters that discussions were continuing on the press statement but council diplomats said they did not expect a response.

Haftar, who holds sway in eastern Libya, launched an offensive in April to seize Tripoli, seat of a UN-recognized government that is backed by various militias.