Palestinian Authority Mahmoud Abbas bypassed US Secretary of State John Kerry last week, sending a letter directly to President Barack Obama about his concerns over peace talks with Israel.

Five Israeli and Palestinian sources revealed to Haaretz that Abbas laid out core Palestinian positions in the letter, as well as his reservations over proposals on security arrangements presented by Kerry in recent weeks.

The decision to go over the heads of Kerry and special envoy Martin Indyk is seen as an indication of Abbas’s growing frustration with the secretary of state. Sources reported that a December 6 meeting between Kerry and Abbas on security arrangements in the Jordan Valley left Abbas fuming, sparking a “real crisis of faith” with the senior US official.

In the letter, Abbas wrote that the Palestinians and Israelis had come to agreement on a plan during Ehud Olmert’s term as prime minister that would place an international force, not the IDF, on the Israeli-Jordanian border. The Palestinians, he said, would be amenable to a phased withdrawal of Israeli forces from the Jordan Valley, but would not countenance an indefinite Israeli presence.

However, ideas floated by Kerry in recent weeks included IDF control of a broad corridor in the Jordan Valley — not just a minimal stationing of Israeli soldiers along the border — for the first 10 years after the signing of a peace deal. Abbas was reportedly even more concerned by the arrangement for the end of that period, which hinged on the Palestinians meeting certain benchmarks, something he felt would give Israel a veto over the IDF withdrawal from a future Palestinian state.

Despite the reports, chief PA negotiator Saeb Erekat denied that Kerry had presented a proposal on security arrangements in the West Bank, according to the Palestinian Ma’an news agency. “Kerry did not propose any plan for the Jordan Valley and most of what was published about this issue is a figment of journalists’ imagination,” Erekat stressed. “Perhaps they are speaking about meetings in their imagination.”

Palestinian officials have accused Kerry of being biased toward the Israelis, especially in light of a perceived risk to Israel in the recent nuclear deal with Iran. At the same time, some Israelis involved in the talks feel that the secretary is more amenable to the Palestinian position.

Sources indicated that Abbas wrote the missive in the hope of shaping the framework agreement the Obama administration is expected to present in late January 2014. He did not publicize the letter out of a desire to avoid antagonizing Kerry.

The PA president considered sending a personal letter directly to Obama, but settled on an unofficial memorandum instead.

A spokesperson for the US National Security Council declined to comment on the correspondence.

The presence of Israeli soldiers in the Jordan Valley in a final agreement is also a point of contention between Netanyahu and his chief negotiator, Justice Minister Tzipi Livni.

According to a September report in the Israeli daily Maariv, Livni supports the introduction of international forces to the Jordan Valley, similar to the expanded role UNIFIL received in southern Lebanon under Security Council resolution 1701, which ended the Second Lebanon War in 2006, and which Livni was appointed by the government to oversee.

Netanyahu, however, adamantly opposes international forces, insisting on an Israeli presence in the Jordan Valley even within the framework of a Palestinian state.

The prime minister recently ordered the government to begin construction on a major upgrade of the existing security fence along the Jordanian border, including the section of the border inside the West Bank.

Concerned that a final status agreement may not be possible by the nine-month target that the two sides accepted when they resumed talks in August, Kerry in his recent visit aimed to push forward a framework accord that would contain the principles of a comprehensive pact, but not specific details.

If an outline were achieved, the negotiations could be extended beyond the nine-month timeline originally set by Kerry. US officials stressed that an agreement on all issues is the US’s number one goal for the Israeli-Palestinian negotiations.

But should that prove unworkable, they said a framework agreement would buy time for additional negotiations. A framework accord, the officials said, would be a “logical step” on the path to a final status agreement.

AP and Times of Israel staff contributed to this report.