US Secretary of State John Kerry extended for a third day on Saturday his shuttle diplomacy between Israeli and Palestinian leaders, raising speculation of progress in reviving long dormant “peace talks.”

In a sign of Kerry’s desire to keep negotiating, AFP reported, he paid a rare visit to Jerusalem during Shabbat – the sabbath day.

Kerry arrived just before sundown to see Peres, with aides warning that the two would have been obliged to cancel a photo opportunity after the sabbath began at around 7:15 pm. Peres, realising that they were cutting it close, quipped that the sabbath began at 7:30 pm in Tel Aviv and said: “Let’s do a Tel Aviv Shabbat.”

In a commute to which he has grown accustomed, Kerry was scheduled to take a helicopter from Jerusalem to Amman to see Palestinian Authority chairman Mahmoud Abbas before returning in the evening to follow up with Israeli leaders.

In a potential sign of headway, AFP added, Kerry cancelled a dinner he had scheduled for Saturday night in Abu Dhabi, part of his separate tour in the past week through Gulf Arab states to coordinate support for rebels in Syria’s civil war.

Kerry spoke by telephone with the UAE foreign minister, Sheikh Abdullah bin Zayed al-Nahayan, to convey his regrets about the cancellation and to tell him that he hoped to visit at a later date, State Department spokeswoman Marie Harf said.

Harf said that Kerry would still head to a meeting of Asian ministers in Brunei starting on Monday but called off the Abu Dhabi stop because his “meetings on the peace process remain ongoing”.

It was a rare public comment on Kerry’s talks, with US officials saying that they planned to keep quiet about all discussions behind closed doors due to the fluid diplomacy. Kerry is likely to speak before leaving the region.

Kerry has spent seven hours since Thursday sounding out Israeli Prime Minister Binyamin Netanyahu. Their two evening meetings took place at a hotel suite with sweeping views of Jerusalem named after Yitzhak Rabin.

Kerry’s aides have played down expectations of an imminent breakthrough and instead are hoping to make incremental progress to set the stage for substantive negotiations between Israel and the Palestinians.

The contents of the meeting were not disclosed, but an American official was quoted by Voice of Israel public radio as having said that the meeting was “detailed and meaningful.” The two agreed to meet for a third time on Saturday night.