JERUSALEM, Israel (AFP) — Israel has told the Palestinians that a planned release of 26 prisoners cannot proceed, placing already embattled peace talks in further jeopardy after both sides took steps Washington called “unhelpful”.

Israel’s chief negotiator with the Palestinians has told them that the planned release cannot go ahead, a source close to the embattled talks told AFP yesterday.

A frustrated US Secretary of State John Kerry earlier demanded that recalcitrant Israeli and Palestinian leaders demonstrate leadership in the crisis-hit peace process.

Speaking on condition of anonymity, the source said Justice Minister Tzipi Livni told a meeting with her counterparts on Wednesday that the prisoner release could not happen because the Palestinians had resumed a diplomatic campaign meant to challenge Israel more fully in the international arena.

The talks hit a new impasse when Israel failed to free the prisoners as expected at the weekend.

In response, the Palestinians formally requested accession to several international treaties.