After a turbulent summer, emerging markets face another threat: $80 oil.

Currencies in the developing world have been hit by a toxic mix of global trade tensions, a strong dollar and rising U.S. interest rates. That is making dollar-denominated crude all the more expensive as it climbs to four-year highs.

The price of Brent crude, the international oil price gauge, has risen by 22% this year. But the cost has doubled if you’re buying in Turkish lira. It is up 39% in Indian rupees and 34% in Indonesian rupiah.

Emerging-market countries and central banks are being forced to act.

India, the world’s third-biggest oil importer, is weighing temporarily limiting oil imports, while Brazil and Malaysia have introduced fuel subsidies. On Thursday, central banks in Indonesia and the Philippines raised interest rates to tame rising inflation.