Rupiah Strengthens to Rp17,640: What Drove the Gain?

The Indonesian rupiah strengthened to Rp17,640 per US dollar on Monday, September 7, 2026, after trading at Rp17,642 earlier in the session, according to currency and commodities analyst Ibrahim Assuaibi. Rising tensions between the United States and Iran were identified as a key external factor contributing to the rupiah's gain.

On Saturday, the US military reportedly attacked three Iranian oil tankers as Iranian forces allegedly targeted a US Navy vessel with ballistic missiles. Tehran counterclaimed responsibility for downing a US drone and threatened harsher retaliation against further US strikes. This heightened geopolitical risk led to increased market anxiety about the safety of commercial shipping and energy transit through the Strait of Hormuz.

Apart from geopolitical concerns, investors were closely tracking US economic data, with the US labor market absorbing more workers than anticipated. The unemployment rate fell to 4.1 percent in August, below the Federal Reserve's downward revision from 4.5 percent. The robust labor market may shift Federal Reserve focus back to inflation trends, prompting investors to closely watch the release of US Consumer Price Index and Producer Price Index data during the week.

If both indices indicate elevated inflation, potential Fed policy changes ahead of the September FOMC meeting will once again be of market concern. Domestically, this week presents a test of Indonesia's monetary policy flexibility. The government and Bank Indonesia must ensure stimulus measures do not weaken the rupiah or trigger capital flight.

Market participants are also assessing the impact of recent natural disasters, such as the eruption of Mount Anak Krakatau and peatland blazes in Kalimantan and Sumatra, on economic activity and supply chains.