AMMAN, Jordan — A separate truce for southern Syria, brokered by the U.S. and Russia, is meant to help allay growing concerns by neighboring Jordan and Israel about Iranian military ambitions in the area, including fears that Tehran plans to set up a disruptive long-term presence there.

Such apprehensions were stoked by recent movements of Shiite Muslim militias – loyal to Iran and fighting alongside Syrian government forces – toward Jordan’s border with Syria, and to another strategic area in the southeast, close to where the two countries meet Iraq.

The advances are part of Syrian President Bashar Assad’s push to regain territory from rebel groups, some backed by the West, in the southern Daraa province, and from Islamic State extremists in the southeast, near the triangle with Iraq.

But Syria’s neighbors suspect that Iran is pursuing a broader agenda, including carving out a land route through Syria that would create a territorial continuum from Iran and Iraq to Lebanon.

The cease-fire for southern Syria, set to start at noon Sunday, is meant to keep all forces pinned to their current positions, said Jordan’s government which participated in the talks.

This would prevent further advances by forces under Iran’s command, including Lebanon’s Hezbollah militia.

The truce is to be monitored through satellite and drone images as well as observers on the ground, a senior Jordanian official said Saturday, speaking on condition of anonymity because he was not authorized to discuss details with reporters. Syria ally Russia is to deploy military police in the area.

Information on truce compliance could be shared and discussed in different locations, including Jordan, the official said. Israel did not participate in the truce talks, but was presumably briefed by the U.S., the Jordanian official said.

Cease-fires have repeatedly collapsed in Syria’s six-year-old civil war, and it’s not clear if this one will last. The southern Syria truce is separate from so far unsuccessful efforts by Russia, Turkey and Iran to set up “de-escalation zones” in Syria, including in the south.

Israel is expected to watch for truce violations.

Israel has repeatedly said it will not allow Iran to set up a permanent presence in Syria. Israel has carried out a number of airstrikes in Syria against suspected shipments of “game-changing” weapons bound for Hezbollah.

“The question and concern is of course if it will be exploited by the Syrian regime, Hezbollah and Iran to create new facts on the ground,” said Chagai Tzuriel, the director general of Israel’s Intelligence Ministry.