U.S. official says sequencing of agreed steps will be a key issue in upcoming talks with Iran.

OCBC Group Research strategists say the Fed's persistent hawkish stance should constrain near-term upside for Asian currencies versus the dollar, particularly low-yield and US-Treasury-sensitive FX such as the Thai baht (THB), South Korean won (KRW) and, to a degree, the Singapore dollar (SGD). They added falling oil prices partly offset those pressures by easing current account and inflation strains for oil-importing currencies including the Indian rupee (INR), Philippine peso (PHP) and Indonesian rupiah (IDR).

Sources say Russia plans to begin importing gasoline by sea in June to ease domestic shortages.