The dollar firmed on Tuesday, as investors assessed an apparent deadlock in talks between the U.S. and Iran as well as a raft of central bank interest rate decisions this week.

At 16:52 ET (20:52 GMT), the U.S. dollar index, which tracks the greenback against a basket of six major peers, rose 0.2% to 98.64.

Gold prices dipped on Monday, as investors were cautious following a diplomatic setback between the U.S. and Iran and ahead of a key Federal Reserve interest rate decision later this week.

At 15:45 ET (19:45 GMT), spot gold was down 0.6% to $4,681.39/oz, while gold futures fell 1% to $4,694.61/oz.

Goldman Sachs says the U.S. dollar outlook is being shaped by an unexpectedly muted supply shock from ongoing Middle East disruptions, even as energy markets remain a key risk for FX.

In a note, the bank describes the situation as “the curious case of the shrinking supply shock,” arguing that while higher energy prices and product shortages are reshaping global balances, the real economic impact has so far been less visible than initially feared.

Oil prices whipsawed in volatile trade on Friday, but were higher on the week, as traders weighed supply disruptions against the potential restart of peace talks between the U.S. and Iran that could help limit those disruptions.