America’s secretary of state John Kerry concluded his meetings with Palestinian Authority president Mahmoud Abbas on Friday with a last-minute commitment to return to peace talks with the Israelis. The agreement, which came after four days of intense shuttle diplomacy by Kerry, could lead to proper negotiations in Washington DC next week, the first in five years.

Kerry, who has made the Israeli-Palestinian conflict a defining issue during his tenure, was upbeat with reporters after his midnight meeting with Abbas. “I’m pleased to announce that we have reached an agreement,” he said. “This is a significant, and welcome, step forward.”

Kerry’s work got an added boost during his travels to the region on Wednesday when the foreign ministers of the Arab League expressed full support for his efforts. The body earlier toned down its own peace initiative to Israel, promising a regional agreement among the Arabs that would grant the Jewish state full recognition in exchange for territorial concessions to the Palestinians in East Jerusalem, Gaza and the West Bank.

Analysts and Middle East watchers predicted that the Arab League statement could persuade the Palestinians to give diplomacy another try. This appears to have been the case after a difficult few hours of discussions among Palestinian officials as to whether Kerry’s parameters should be expanded upon.

From the outside, it is nearly impossible to determine President Abbas’ state of mind. All of the dialogue is taking place behind closed doors, outside the public’s view and without a full understanding of what John Kerry’s plan is. The Palestinians have long argued that direct negotiations with Prime Minister Benjamin Netanyahu’s government in Jerusalem would be a waste of time unless it agreed to freeze Jewish settlement construction beforehand and guaranteed that a Palestinian state would be allowed to exist within the borders of 1967. Netanyahu has consistently rejected both preconditions.

The United States, with John Kerry in the lead, tried to find some way to split the difference to get negotiations back on track. His efforts might have succeeded at this early stage through a combination of determination and creativity. It has been rumored that Netanyahu agreed to stop all settlement building in the West Bank for the duration of the talks and that some Palestinian prisoners would be released.

Despite the breakthrough, real success can only occur when Abbas and Netanyahu meet in person. The participants of next week’s conference will be Israel’s justice minister Tzini Livni and Palestinian negotiator Saeb Erekat — an indication that the two leaders remain skeptical of Kerry’s plan.

But Kerry and his allies have done their part. Now it is up to Israel and the Palestinians to determine how far they are willing to go in the process and whether they are ready solve a conflict that has long seemed unsolvable. There are a number of big unknowns, such as whether Abbas and Netanyahu are able to moderate their negotiating positions, that could make or break the talks. And the process itself, like past efforts at peacemaking between Israel and Yasser Arafat, will be incredibly painful for all participants.

Nevertheless, when both parties are leaning toward speaking in the same room, it is the best news that proponents of Middle East peace have had since the last serious attempt in 2008.