BEIRUT — Syrian President Bashar Assad said in remarks broadcast Wednesday that Western support for “terrorism” in his country’s civil war is causing the refugee crisis in Europe.

In an interview with Russian media, the embattled leader warned that backing his multifaceted opposition – which he routinely lumps together as terrorists – would only drive more Syrians into European countries. He also warned the United States and foreign opponents that pressuring him to step down from power would fail.

The defiant remarks come as Russia increases support for Assad’s beleaguered military, which has lost substantial territory over the last year. Russia has been a crucial backer of the Syrian president during a 4-year-old conflict that has killed 250,000 people and caused a refugee crisis in Europe.

“If you are worried about them, stop supporting terrorists,” said Assad, referring to Europe-bound Syrians. “This is the core of the whole issue of refugees.”

He described U.S. and European criticism of his policies as “propaganda” that will create “more refugees.”

Monitoring groups and analysts say that attacks by Syrian government forces are a primary cause of the refugee crisis. They say that such attacks – including air raids near Damascus last month that killed more than 100 people in a single day – are killing scores of civilians.

Assad’s remarks struck a far more confident tone than a speech he gave in July in which he acknowledged military defeats because of manpower problems in his military. Extremist groups like the Islamic State and Syria’s al-Qaida affiliate, Jabhat al-Nusra, have made sweeping advances in the country. Assad now controls less than half its territory.

In the interview, he did not mention Russia’s buildup in Syria but called Moscow an “impartial” player in the conflict.

In addition to military advisers and technicians, the Russians have sent tanks and heavy weapons to Syria.