Jakarta. The rupiah depreciated against the US dollar on Monday, following US President Donald Trump's announcement of new tariffs on all steel and aluminum imports, including from Canada and Mexico.

The rupiah closed 75.5 points lower, depreciating by 0.46 percent to Rp 16,358 per US dollar. Meanwhile, the US dollar index rose 0.27 points to 108.3. This marked a reversal from Friday’s session when the rupiah gained 58.5 points to close at Rp 16,282 per US dollar.

Currency analyst Ibrahim Assuaibi from Laba Forexindo Berjangka said that Trump’s decision to impose a 25 percent tariff on all steel and aluminum imports has sparked concerns over escalating trade tensions and their potential impact on the global economy.

"China's retaliatory tariffs on US goods, effective today, have further contributed to weak market sentiment," Ibrahim said on Monday.

On Sunday, Trump said the US was making progress with Russia to end the war in Ukraine but declined to provide specifics about any communications with Russian President Vladimir Putin.

Sanctions imposed on Russian oil trade since Jan. 10 have disrupted Moscow's supply to key clients, including China and India. Additionally, the US escalated pressure on Iran last week, with the Treasury Department issuing new sanctions against individuals and tankers involved in shipping millions of barrels of Iranian crude oil to China annually.

Investors are also closely watching inflation data from China. January’s Consumer Price Index (CPI) showed moderate growth, while the Producer Price Index (PPI) experienced a consistent decline, signaling continued weakness in household spending and industrial activity—two key drivers of economic growth.

"Markets are eyeing China's policy response. Weak inflation could push Beijing to implement additional stimulus measures, such as interest rate cuts or infrastructure spending, to boost its sluggish economy," Ibrahim explained.

For Tuesday’s trading session, Ibrahim predicted the rupiah would remain volatile, with a potential closing range between Rp 16,340 and Rp 16,410 per US dollar.