New Delhi: Headline inflation rose to 9.44 percent in June on the back of rising prices of fuel and manufactured products, which may prompt the Reserve Bank to raise key rates again in its quarterly policy review later this month.

Inflation, as measured by the Wholesale Price Index (WPI), stood at 9.06 percent in May. It was 10.25 percent in June, 2010.

Meanwhile, as per data released by the government on Thursday, the overall inflation figure for April this year has been revised upward to 9.74 percent from the provisional estimate of 8.66 percent.

The rise in inflation can partly be attributed to the hike in prices of diesel, cooking gas and kerosene announced by the government on May 24.

The higher prices of petroleum goods, according to experts, are adding to supply side constraints.

The index for the fuel and power segment, which has a weight of almost 15 percent in the WPI basket, stood at 12.85 percent year-on-year in June. This was up from 12.32 percent in the previous month.

LPG became 12.17 percent more expensive on an annual  basis, while high speed diesel was up 6.58 percent. Petrol, whose prices were hiked in April, also became dearer by 30.61 percent.

Prices of manufactured products, which have a weight of around 65 percent in the WPI basket, went up by 7.43 percent year-on-year in June.

Inflation in manufactured products has been steadily rising since February this year, when it crossed the 6 percent mark. It was 7.27 percent in May.

During the month under review, primary articles witnessed inflation of 12.22 percent on an annual basis, as against 11.30 percent in the previous month. Primary articles have a share of around 20 percent in the overall WPI basket.

Within the primary articles segment, food articles became 8.38 percent more expensive, while prices of non-food primary articles went up by 18.57 percent.

The RBI has already hiked key policy rates ten times since March, 2010, to curb demand and tame inflation. With headline inflation remaining high, as shown by the latest numbers, it may go in for another hike at its July 26 quarterly review.

Experts have said that such action is inevitable and the RBI had also maintained that taming inflation was a priority for the central bank.

However, the latest numbers are in line with the RBI's projection of a high inflation rate in the first half of the fiscal.

In its monetary policy for 2011-12, the central bank had said that continued high prices of global commodities, particularly oil, would continue to drive the rate of price rise.

The RBI had projected inflation to average 9 per cent for the first six months of 2011-12 before moderating to around six percent by the year-end.

Both the RBI and other experts had also said that inflationary pressure during the next few months would be more from commodity prices, rather than on account of food items, as was the case in 2010.

Headline inflation has been above 8 percent since January, 2010.