* Producer input price inflation rises to 9.5 percent y/y
* Producer output price inflation eases to 4.4 percent y/y
* Higher wheat prices push up food costs
(Adds reaction, comment)
By Christina Fincher and Fiona Shaikh
LONDON, Oct 8 (Reuters) - Higher wheat prices led to a sharper than expected rise in British manufacturers' raw materials costs last month, while annual factory gate inflation slowed less than expected, official data showed on Friday.
The figures will disappoint Bank of England policymakers at a time when consumer price inflation is running more than a full percentage point above the bank's 2 percent target.
The Office for National Statistics said producer input prices rose 0.7 percent on the month in September, almost double analysts' expectations, and raising the annual rate to 9.5 percent from 8.7 percent in August. That was the biggest monthly rise in the annual rate since April.
Output price inflation eased for a fifth consecutive month to 4.4 percent year-on-year from 4.7 percent in August. The decline was smaller than expected but still took factory gate inflatio n to its lowest in seven months.
The pound rose after the figures as markets speculated that stubborn inflation pressures lessened the likelihood the Bank of England would adopt any further monetary easing to shore up the economic recovery.
"When you are in an environment where inflation has been above target for so long, signs of greater price pressures at any stage of the production process are worth listening to," said Philip Shaw, economist at Investec.
"So this release may have a part to play, albeit a modest one, in assessing whether the Monetary Policy Committee provides more quantitative easing in due course."
SPLIT
British consumer price inflation has proved to be surprisingly resilient this year, forcing BoE Governor Mervyn King to write several letters of explanation to the government.
The central bank is convinced that high inflation is largely due to temporary factors and will fall back over the course of the next two years.
However, the outlook remains highly uncertain, and has been the subject of vigorous debate on the MPC. One member, Andrew Sentance, has been calling for higher interest rates since June, but his colleague Adam Posen argued last week that there was a strong case for pumping more money into the economy.
The BoE opted to leave interest rates on hold at a record low 0.5 percent on Thursday and left the stock of its asset purchase programme unchanged at 200 billion pounds.
Minutes to the meeting later this month will reveal whether Sentance or Posen were able to win other policymakers round to their view.
Higher cereals prices contributed to a rise in the annual rate of inflation of domestically-produced food to 9.9 percent, its highest since October 2008.
Wheat prices have risen strongly in the summer as a result of a drought in major producer Russia.
Crude oil input prices fell slightly on the month but still exerted strong upward pressure on the annual rate.
(Editing by Patrick Graham)