Ali Shamkhani, the head of Iran’s Supreme National Security Council (SNSC), has warned the United States and Saudi Arabia against sending military forces to Syria, the reports. He cautioned that the presence of any foreign troops in Syria will be seen as an act of “invasion” and “support for terrorist elements” in the country. Shamkhani, who is a senior advisor to Iran’s Supreme Leader Ali Khamenei, also accused Washington and Riyadh of backing terrorist groups in Syria. “The American government and al-Saud leaders not only do not take any action to fight terrorism, but their support for them [terrorists] prepares the ground for their activities,” he added.

Comment: The Iranian official’s remarks are a reaction to this week’s meeting between President Donald Trump and Deputy Crown Prince Mohammad bin Salman. In the past three days, the Iranian state-controlled and semi-official media outlets have expressed the concern that Riyadh is improving its relations with the new U.S. administration in order to push back against the Iranian regional agenda. This comes at a time when Iranian leaders are concerned that Riyadh’s latest outreach to Muslim-majority countries in the Asia-Pacific region as well as to Middle Eastern states – particularly Iraq – is aimed at isolating the Islamic Republic.

Shamkhani’s warning on Syria also indicates that Iranian leaders are worried that the Trump administration and its regional allies may escalate their involvement in the Syrian conflict at the expense of Tehran’s interests. Shamkhani issued the warning just a day after Prince Mohammed – following his meeting with U.S. Defense Secretary James Mattis – that Riyadh would consider sending ground troops to fight inside Syria. "We are ready to do anything that will eradicate terrorism, anything without limits," the Saudi leader told reporters.  Recently, Iranian leaders have also warned that the consequences of Washington establishing safe zones inside the Syrian territory would be dire.  “If some parties constantly pursue the exclusion of Syria’s legitimate president and the creation of a power vacuum in the country, or take steps to divide the country by plans such as setting up safe or buffer zones, they will actively strengthen terrorism and prolong the crisis in the region,” Shamkhani said on February 1, just days after President Trump emphasized he "."

The growing anxiety in Tehran about the Trump administration’s Iran policy also stands in stark contrast to initial expressed by Iranian leaders and state-run media before Donald Trump took office on January 20. During the U.S. election campaign, many Iranian leaders expressed the hope that then-candidate Trump’s favorable view of Russian President Vladimir Putin and the Trump team’s eagerness to work with Moscow in the war on terrorism might benefit Iran’s agenda in Syria and in the broader region. But that optimism began to fade quickly as the Trump administration adopted an aggressive approach vis-à-vis Iran, by including the Islamic Republic in the travel ban, imposing new sanctions on Iranian entities, and warning Tehran over its controversial ballistic missile test.