The sources, who spoke to Reuters on condition of anonymity, said that the behaviour of the Israeli mediators revealed “internal discord”.
According to the sources, the Israeli delegation would give approvals on several conditions under discussion, but then come back with amendments or introduce new conditions that risked sinking the negotiations.
The sources added the mediators viewed the “contradictions, delays in responses, and the introduction of new terms contrary to what was previously agreed” as signs the Israeli side viewed the talks as a formality aimed at influencing public opinion.
Earlier, Deputy Head of Hamas in the Gaza Strip Khalil Al-Hayya told Al Jazeera the Palestinian movement has been flexible in seeking a deal to end the war in Gaza, adding that Prime Minister Benjamin Netanyahu is not looking for an agreement or the release of Israeli captives.
Israel and Hamas have been engaged in indirect talks since January to reach an agreement that ends the war on Gaza and swaps prisoners.
Israel’s war on Gaza, now nearing its tenth month, has destroyed large swaths of the besieged territory.
More than 38,400 people have been killed, the great majority of them women and children. Thousands more are missing or presumed to be dead under the rubble.