By David Milliken and Fiona Shaikh

LONDON, Nov 5 (Reuters) - British manufacturing output rose faster than expected in September, and at its quickest monthly pace since July 2002, rebounding from a sharp drop in August, official data showed on Thursday.

The figures come just hours before the Bank of England will announce whether it is going to expand its 175 billion pound quantitative easing programme and add to the raft of conflicting data about the British economy over the past month.

The Office for National Statistics said factory output rose 1.7 percent in September, almost reversing a 2.0 percent decline in August. September's outcome was much higher than economists' forecasts of a 1.0 percent and the biggest gain since July 2002.

However, the ONS said the figures on their own would not lead to any significant change to its estimate of third-quarter GDP, which shocked analysts last month when it showed a 0.4 percent fall in economic output between July and September.

'Things have been very erratic and it's hard to say whether this represents the beginning of a bounce back,' said Stephen Lewis, chief economist at Monument Securities.

Market reaction to Thursday's data was muted, with investors focusing on the BoE's policy decision at 1200 GMT.

The ONS said 10 of the 13 manufacturing sub-sectors posted gains in September, with electrical and optical equipment, transport equipment and other manufacturing recording the strongest increases.

The wider industrial output measure, which includes power generation and natural resource extraction, rose 1.6 percent in September, again the strongest rise since July 2002 and beating forecasts for an increase of 1.0 percent.

The ONS said the increases came after factories reopened following an August break which had depressed output in that month.

The CIPS/Markit manufacturing PMI survey earlier this week pointed to a further rebound in manufacturing activity in October, although it had suggested a very slight contraction of activity in September.

Year-on-year, the ONS said manufacturing output fell 9.3 percent and industrial output was 10.3 percent lower.

In the three months to September, industrial output dropped 0.8 percent, roughly in line with the 0.7 percent estimate used in last month's preliminary Q3 GDP data.

(Editing by Mike Peacock) Keywords: BRITAIN MANUFACTURING/

(uk.economics@reuters.com, Tel: +44 207 542 5109)

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