A representative of a left-wing faction fighting alongside the Islamist Hamas movement in Gaza has told Newsweek his group is open to a temporary ceasefire in their war with Israel and called for greater efforts to establish a unity government among different Palestinian parties.

Hayya, said in a pre-recorded speech on Thursday the group had not rejected the latest U.S. proposal for a ceasefire with Israel but demanded changes that would secure the end of the war in the enclave.

The latest friction in negotiations comes as the fighting nears 20 months of war, and as desperation grows among hungry Palestinians and relatives of hostages in Gaza.