Jordan's King Abdullah and US Defence Secretary Lloyd Austin have discussed the expansion of military co-operation between the two countries.
The kingdom is focused on thwarting the smuggling of drugs into the country from Syria, a threat which it blames on pro-Iranian militias.
“The meeting covered the strategic partnership between Jordan and the United States, as well as prospects for expanding defence co-operation,” the palace said.
It said King Abdullah “expressed pride in the deep-rooted ties of friendship and the strong military partnership between the two countries”.
The meeting on Sunday was the start of a Middle East tour by Mr Austin, aimed at showing US engagement in the region amid a tougher American stance on Iran.
Mr Austin will also visit Israel and Egypt in a show of support for Washington's main regional allies.
King Abdullah also called for more efforts “to create a political horizon” to relaunch Israeli-Palestinian talks, after Jordan hosted a meeting towards this goal in Aqaba last month.
Jordan, which has a defence pact with Washington and relies on US and European aid, refrains from public criticism of Iran and has diplomatic channels with Tehran.
However, starting last year, the kingdom began to blame pro-Iranian militia operating along Syria's border with Jordan for the increase in drugs — particularly stimulant pills known as Captagon — smuggled into the kingdom.
Mr Austin's visit comes only a day after Gen Mark Milley, chairman of the US Joint Chiefs of Staff, made a rare visit to the US sphere of influence in Syria, where Russian and Iranian intervention over the past decade has been instrumental in supporting President Bashar Al Assad.
The US Defence Department said before the visit that discussions would focus on regional stability and advancing multilateral security co-operation with integrated air and missile defences.
Central to discussion will be the “full constellation of Iran-associated threats”, a senior defence official was quoted as saying on the Pentagon’s official site.
Those threats include Iran's “arming, training and funding of violent proxy groups, aggression at sea, cyber threats, its ballistic missile programme and drone attacks”.
In Israel, Mr Austin will also raise concerns about the surge in violence in the occupied West Bank that has alarmed Jordan and Arab leaders.
He will discuss diplomatic efforts to reduce tension before the Ramadan and Passover seasons, US officials said.