The OECD said Wednesday that the Federal Reserve should hold back from quickly raising interest rates, as the US central bank was holding a meeting that could signal a hike may be just a couple months away.

"Lower oil prices and the appreciation of the dollar make it appropriate for the Federal Reserve to wait longer to raise policy interest rates," said the OECD as it released an update to its outlook for the global economy.

The Fed has been signalling for months that an increase in the benchmark federal funds rate from zero, where it has been stuck for six years of crisis and recovery, could come as early as mid-year.

Investors will be looking at the statement following the end of the two-day Federal Open Market Committee meeting on Wednesday for any changes in language which indicate whether a recent soft spot in the economy and the soaring dollar have changed the timing for a rate increase.

The dollar has been quickly rising in value in anticipation of a rate hike, but the appreciation could slow US exports and growth.

The OECD held its forecasts for US growth steady at 3.1 percent this year and 3.0 percent in 2016.

Most bets are that the FOMC will confirm its path toward a June or July Fed funds increase by removing from its policy statement the sentence that it still "can be patient" before normalizing policy.

Fed Chair Janet Yellen has said that the increase could come within two FOMC meetings of removing that phrase, which from Wednesday would point to June at the earliest.