Emerging market stocks lost steam on Wednesday, slipping for the first time in four sessions, while developing world currencies held an even keel as investors awaited the U.S. Federal Reserve's rate decision and outlook due later in day.

While markets have almost fully priced in the Fed standing pat on borrowing costs, a boost in sentiment on hopes of the outlook from the Fed being more dovish than earlier expected seemed to have run its course.

"I think when you look at the meeting today, it is of course a question of how dovish they will be," said Morten Lund, an analyst with Nordea Markets.

"If you look at markets right now, it's almost like they are pricing a rate cut (rather) than a hike. I don't think we will see zero hikes for 2019 in the 'dot plot'," Lund said, referring to the diagram showing individual policymakers' views on rates in the future.

Markets broadly expect the dot plots from today's meeting to show one rate hike this year, down from two earlier expected.

MSCI's benchmark of developing world stocks edged 0.1 percent lower, but were not far from Tuesday's near 6-1/2 month peak. Equities in index heavyweight China.CSI300 marked time, while their more liquid peers in Hong Kong dropped half a percent.

Russia's rouble firmed a little less than 0.2 percent, while local equities  fell as gains among energy stocks on higher oil prices were broadly negated by losses in other sectors. 

While the oil/rouble correlation is not as strong as it once was, the rouble has reflected a chunk of the 9 percent increase in oil prices since the last Russian central bank rate meeting on Feb. 8.

All 26 analysts polled by Reuters expected the bank to leave the key rate unchanged at 7.75 percent at its next meeting on Friday.

South Africa's rand dipped, while local stocks slid 0.3 percent, distancing themselves from a near six-month closing high recorded in the previous session.

Yields on the commodity producer's local 10-year bonds hit their highest in nearly a month at 8.825 percent, as issues at utility Eskom weighed on sentiment. 

Data on inflation in February is due later in the day, ahead of a central bank meeting next week where borrowing costs are expected to be left untouched. 

In emerging Europe, the Czech crown was 0.1 percent softer against the euro.

Kazhakstan's tenge was 0.6 percent weaker as it extended losses from the previous session, a day after the surprise resignation of President Nursultan Nazarbayev, who had led the oil-rich country for about three decades.

(Reporting by Aaron Saldanha in Bengaluru Editing by David Holmes) ((Aaron.Saldanha@thomsonreuters.com; +91 80 6749 1130; Reuters Messaging: Aaron.Saldanha@thomsonreuters.com@reuters.net))