Despite what US Secretary of State John Kerry termed as “constructive talks” in his bid to revive negotiations between Israel and the Palestinians this week, indications from both sides Wednesday pointed to an unwillingness to go along with the parameters of the US initiative.

Senior officials quoted in Israeli media late Wednesday said Israel had taken issue with a number of parts of Kerry’s plan, including pre-negotiations on goodwill gestures and the shape the talks would take.

The reports came hours after Palestinians said they would only come to the table in exchange for “a clear formula” concerning final borders and the release of detainees in Israeli jails, underscoring the fragility of US efforts to jump-start peace talks after a two-and-a-half year hiatus.

Kerry left the region on Tuesday, after several days of talks with Israeli and Palestinian leaders. Press reports indicated that he had offered the Palestinians a package of Israeli good-faith concessions in exchange for a return to the negotiation table.

Speaking to reporters before flying to London Tuesday, Kerry stressed that he was being mindful of the “good intentions and failed efforts” that have dogged Middle East diplomacy in the past and said he would focus on “laying the groundwork so we can bring people to the table with a clear understanding of what we’re beginning on, what we’re trying to do, and where we’re trying to end up.”

But a senior Israeli official told news website Ynet Wednesday that Jerusalem had no intention of providing the Palestinians with any concessions ahead of talks, which had reportedly been a keystone of Kerry’s efforts.

“Ministers are unanimous over the decision of not giving in to any precondition. [The Palestinians] present conditions in order to make the process of renewing direct talks difficult. There will be no gestures, especially not land withdrawals,” the unnamed source told Ynet.

On Monday, the Palestinian Ma’an news agency reported that Kerry had told Palestinian Authority President Mahmoud Abbas that Israel was willing to transfer some West Bank land to PA control as a pre-talk good faith measure.

Another senior official told the Haaretz newspaper Wednesday that Israel had taken issue with the idea that talks with Palestinians would initially only focus on borders and security.

Kerry is expected to spend the next several months engaging in a type of shuttle diplomacy to push the sides closer together. Talks between the sides have been frozen since 2010, at the tail end of a 10-month moratorium on Israeli settlement construction.

The Palestinians say they want another freeze before coming to the table while Israel has called for talks without preconditions.

US President Barack Obama, during his visit in March, endorsed Israel’s position in favor of new talks without preconditions. Still, Abbas is understood to be demanding assurances that Israel is prepared in principle to relinquish 100 percent of the West Bank, with various one-for-one land swaps to enable Israel to keep key settlement blocs.

Palestinian sources said Abbas wants to see an Israeli map setting out Netanyahu’s territorial positions up front, which the prime minister refuses to provide, believing it will be seized upon by the Palestinians as the basis for new territorial demands.

The Associated Press contributed to this report.