The U.S. military will not openly confront Iran, but will instead use indirect means to limit its expansion in Syria, a top commander said this week, as Western nations consider stepping up their response to Tehran’s support for armed groups across the Middle East.

Gen. Joseph Votel, who heads U.S. Central Command, said that U.S. support for government troops in Iraq and a Kurdish-dominated partner force in Syria could help ensure that Tehran is unable to freely smuggle supplies and personnel into Syria, where Iranian-backed forces are fighting in support of Syrian President Bashar al-Assad.

“This is one of the ways that we can begin to impede Iran’s malign activities,” Votel said in a phone interview. “There are some things we can do that are indirect that we’re able to accomplish really within the confines of our defeat-ISIS mission that we have ongoing.”

ISIS is another name for the Islamic State, the group the U.S. military has been battling in Iraq and Syria since 2014.

While military leaders, concerned about being dragged into Syria’s broader civil war, have sought to tightly focus their mission there on extremists, they have also watched with concern as Iran has ramped up support for militias like Lebanon’s Hezbollah and deployed forces of its own in a bid to keep Assad in power.

Despite those concerns, Votel’s comments indicate a desire across the military leadership to avoid triggering a confrontation with Iran at a time when the Pentagon is hoping to wind down insurgent wars in the Middle East and renew its focus on China and Russia.

The general spoke a day after President Trump, suggesting a possible shift in the U.S. strategy for Syria, hinted that the United States would act to halt Iran’s ability to reach across Syria to the Mediterranean Sea.

“We will have a strong blockage to the Mediterranean, which to me is very important — because if we don’t, you have Iran going right to the Mediterranean. Not going to have that,” Trump said during a visit by French President Emmanuel Macron, who has pushed the U.S. president to take a more expansive view of what Washington can accomplish in Syria.

Macron used his Washington visit to advance a plan he hopes will prevent Trump from pulling out of President Obama’s nuclear deal with Iran, an agreement the American leader has disparaged repeatedly. Under Macron’s proposal, the nuclear deal would be supplemented by a larger agreement addressing Tehran’s ballistic missile activities and seeking to curb its military expansion.

From Lebanon to Iraq and Yemen, Iran has grown its military footprint in the last decade as proxy groups have taken on new political and military clout.

The phenomenon creates particular concern for U.S. policymakers focused on Syria, where Iranian and Russian backing has turned the civil war in Assad’s favor, and in Iraq, where the role of Iranian-backed militias in fighting the Islamic State has given them increased political power.

In addition to Syria, Votel named a number of indirect measures the United States might take across the Middle East, including seeking to deter proxy activity by positioning troops in the region, deploying naval vessels in waters contested by Iran, and providing support to allied nations’ defenses, such as ballistic missiles in Saudi Arabia.

Secondly, Votel said, the U.S. military will seek to build up partnerships with local forces across the region, “making them capable and resilient to deal with the kind of destabilizing activities that Iranians perpetrate.”

Finally, the United States will disrupt Iran’s activities, including by interdicting illicit weapons shipments.

Votel described the results that such indirect measures have had to date on Syria as a “work in progress.”

“It’s a difficult, dynamic, complex environment to work in and something we’re always working on,” he said.

Asked how he would measure U.S. success in checking Iran’s ability to expand further in the region, Votel said he would look at its ability to smuggle weaponry to allied groups and position forces in vulnerable areas.

While most Western officials have abandoned hopes that Assad will be forced from power in the near-term, Votel disputed the notion that the leader’s patron, Iran, would enjoy lasting on-the-ground influence in Syria.

Votel said the ultimate goal of U.S. operations in Syria — although focused primarily on the Islamic State — would be to enable a political solution, he argued, that would check Iran and Russia’s influence there.

“I don’t think we should take it as a foregone conclusion, that the international community has to accept that,” he said. “And I think the political process that we’re all working toward . . . is designed to certainly address that.”