As violence intensifies in nearby Syria, the country of Jordan will hold on to an arsenal of American fighter jets and a sophisticated anti-missile system when a multi-nation military drill wraps up later this month.

A United States defense official said on condition of anonymity Thursday that the Pentagon will keep a fleet of F-16 fighter plane and its Patriot anti-missile system in Jordan past the expiration of the 12-day Eager Lion exercise currently underway.

Jordan officials confirmed earlier this month that the US would be deploying the weaponry during the exercises, but a source speaking to Agence France-Presse now says those items will stay overseas indefinitely.

“It was decided the assets would remain in place,” the official told AFP. 

UK media also cite the Times as reporting that 300 US Marines were deployed in Northern Jordan along the Syrian border in addition to the Patriot missile batteries.

The deployment has reportedly been characterized as part and parcel of the training exercise, which is intended to increase regional stability, and not a means of training Syrian rebels or carrying out offensive operations in the country, the daily cites an unidentified US official as saying. 

AFP’s report was published at the same time this week that the US ramped up claims that Syrian President Bashar al-Assad used chemical weapons on his own civilians. The White House told members of Congress Thursday that Assad had crossed a “red line” previously warned of by President Barack Obama, and Washington is expected to soon start providing military aid to Syrian rebels.

A F-16 fighter jet belonging to the U.S. Air Force (Reuters)

According to AFP’s source, the US is seriously weighing an option in which American money will be combined with contributions from other government, including European allies, to give Syrian rebels a way of funding the acquisition of weapons.

“There would be pooled funds. That would enable other countries to draw from the pool to provide weapons,” the official said.

Also an option being considered: implementing a no-fly zone.

"Washington is considering a no-fly zone to help Assad's opponents," an unnamed Western diplomat told Reuters this week. Additionally, senior US officials told the Wall Street Journal that establishing a no-fly zone is indeed an option being heavily considered in Washington.

According to the diplomat, the no-fly zone would be established on Syria’s border with Jordan, likely drawing on the Patriot systems and F-16s being left behind by the Pentagon after Eager Lion.

But while the help from the US is still unknown with regards to both scope and logistics, leaving weaponry in nearby Jordan will likely be America’s first formal contribution to preparing the region for a war that seems to only be increasing in severity. The United Nations says more than 90,000 people have died so far in the two-year-old Syrian civil war, and this week US Deputy National Security Advisor for Strategic Communications Ben Rhodes attributed as many as 150 causalities on the use of poisonous sarin gas. The UN also estimated that more than a quarter-of-a-million Syrians have sought refuge in Jordan as of late.

Speaking to NBC News, Rhodes said the White House is “looking at a wide range of types of support we can provide both to the political opposition and to the SMC,” referring to a principal opposition group in Syria named the Supreme Military Council.

“I'm not going to be able to detail every single type of support that we are providing, but it's suffice to say it's important to note that it is both the political and the military opposition that will be -- that is and will be receiving US assistance,” Rhodes said. 

To Reuters, Rhodes said, "A no-fly zone … would carry with it great and open-ended costs for the United States and the international community. It's far more complex to undertake the type of effort, for instance, in Syria than it was in Libya."

The decisions to begin aiding the opposition and to leave weapons in the hands of Jordan both attracted their fair share of commentary. When it was originally confirmed that the US would be deploying fighter jets and an antimissile system to participate in Eager Lion, a spokesperson for Russia’s Foreign Ministry suggested America take an alternate route.

"We have more than once stated our opinion on this - foreign weapons are being pumped into an explosive region," spokesman Alexander Lukashevich said in a statement.

"This is happening very close to Syria, where for more than two years the flames are burning of a devastating conflict that Russia and its American partners are trying to stop by proposing to hold an international peace conference as soon as possible."

Mohammad al-Momani, Jordan’s minister of information, told Reuters, "These annual exercises will increase the preparedness of the Jordanian army. This year we are in need of more advanced weapons.”

“This exercise provides us with the opportunity to develop relationships and capabilities,” US Maj. Gen. Robert Catalanotti, the Central Command director of exercises and training, told Stars and Stripes.

Armies from at least 18 countries have sent more than 15,000 to Jordan to participate in this month’s annual Eager Lion drill. It is slated to wrap up June 20.

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