KUALA LUMPUR (Bloomberg) - Malaysia's ringgit dropped after Singapore unexpectedly loosened monetary policy, joining a global round of easing amid slowing economic growth and the risk of deflation.

The Singapore dollar fell as much 1.3 per cent against the greenback, the biggest loss since 2010, as the central bank said Wednesday it will reduce the slope of its currency band while sticking with a modest and gradual appreciation. Malaysia's monetary authority meets on today and the consensus in a Bloomberg survey is for no change.

"The ringgit is weakening because of the surprise move by the Monetary Authority of Singapore," said Mr Jonathan Cavenagh, a foreign-exchange strategist at Westpac Banking Corp in Singapore. "That's the main driver."

The ringgit depreciated 0.5 per cent to 3.6142 a US dollar as of 9:31 a.m. in Kuala Lumpur, data compiled by Bloomberg show. The currency slid to 3.6277 on Jan. 21, the weakest level since April 2009.

A plunge in oil prices has made the ringgit Asia's worst-performing currency in the past three months with a 9.5 per cent loss. The nation is the region's only major exporter of the fuel. Mr Cavenagh predicts the ringgit will retreat to 3.65 a dollar in the next few months.

Malaysia will keep its benchmark overnight policy rate at 3.25 per cent, according to all 19 economists surveyed by Bloomberg before the 6 p.m. decision local time. Thailand's central bank also convenes today.

The yield on the nation's 10-year sovereign bonds dropped two basis points, or 0.02 percentage point, to an eight-week low of 3.90 per cent, data compiled by Bloomberg show.