Singapore's annual core inflation rate was unchanged in May from April, official data showed on Monday, as an increase in the cost of services was offset by lower prices of energy and goods.

The core inflation rate, which excludes private road transport and accommodation costs, came in at 3.1% in May from a year ago, slightly higher than the 3.0% forecast by a Reuters poll of economists and unchanged from April and March.

Headline consumer prices in May were up 3.1% from the same month last year, driven by higher private transport prices. The rate was just above than the 3.05% forecast in the poll and compared with an annual 2.7% rise in April.

Core inflation is expected to stay on a gradual moderating trend over the rest of the year and step down more discernibly in the fourth quarter of this year, the trade ministry and Monetary Authority of Singapore (MAS) said in a joint statement.

They maintained their 2024 headline and core inflation projections, expecting the measures to average between 2.5% to 3.5%.

"However, risks to the inflation outlook remain," they said.

"Fresh geopolitical shocks, adverse weather events and further transportation disruptions around the world could put upward pressure on global energy and food commodity prices, as well as shipping costs," they said.

MAS, which uses the exchange rate as its primary tool, is scheduled to next review its policy settings in July.

The central bank has left monetary policy settings unchanged for four consecutive meetings through April.

"Going forward, we expect inflation to continue to ease and the MAS to keep its monetary policy parameters unchanged this year," Goldman Sachs' Rina Jio and Danny Suwanapruti wrote in a research note on Monday..

In May, the trade ministry maintained its economic growth forecast for 2024 at 1.0% to 3.0%.

Gross domestic product grew 1.1% last year, moderating from 3.8% in 2022. (Reporting by Yantoultra Ngui; Additional reporting by Ankur Banerjee and Xinghui Kok; Editing by John Mair, Ed Davies)