A former American ambassador to Syria says the Syrian government and its allies, including Iran, will ultimately frustrate attempts by the United States to influence Syrian matters and will drive the US out of the Arab country.

Robert Ford, who served as the US’s envoy to Syria under former US president Barack Obama, made the remarks in an interview with the London-based Arabic-language newspaper Asharq Al-Awsat on Monday.

He said the US was, first of all, mistaken in giving support to the opposition in Syria back in 2011 and demanding Syrian President Bashar al-Assad’s ouster. Ford said he knew that that expression of support would encourage certain elements of the opposition to take up arms and expect a US invasion against Damascus, which he said would not be forthcoming.

Ford also said that the US would not defend the Kurdish forces it has been supporting so far in case the Kurds engaged in clashes with the Syrian forces.

“[The US] will not defend the Kurds against Assad’s forces,” the former US envoy said. “What we’re doing with the Kurds is not only politically stupid, but immoral.”

“Syrian Kurds are making their biggest mistake in trusting the Americans,” he added.

The US has been backing a mainly Kurdish alliance known as the Syrian Democratic Forces (SDF).

Ford also said that, given the strong support being offered by Iran and Russia to the Syrian government, the “game was finished” for US plans to overthrow Assad or compete with what he said would be Iran’s success in the country.

“The Iranian position will advance,” Ford said.

“Assad won, I mean he’s the victor, or he thinks so,” he added. “Maybe in 10 years, he will retake the entire country.”

Syria has been gripped by unrest since 2011, when militancy first began in the country. Foreign states opposed to President Assad have since then been funding and providing weapons to anti-Assad militants, among them thousands of paid foreign terrorists dispatched to help force Assad out of power.

The Syrian government, however, has been fighting that militancy back, aided in that battle by advisory military support from Iran and Russia. Moscow has also been conducting an aerial campaign against terrorist positions in the Arab country on a request by Damascus.