UK's NIESR sees 0.8 pct GDP growth in Q3

LONDON, Oct 9 (Reuters) - Britain's economy probably grew atits fastest pace in over two years during the third quarter of2012, but it is likely to slow sharply in future, the country'sleading macroeconomic think tank said on Tuesday.

British gross domestic product rose 0.8 percent in the threemonths through September, up from 0.1 percent growth in thethree months through August, the National Institute of Economicand Social Research (NIESR) estimated.

This is a stronger growth rate than the average 0.6 percentexpected by economists in a Reuters poll , although theeconomy is still likely to shrink overall in 2012 due to a sharpcontraction in the first half of the year.

Moreover, NIESR said the strong third-quarter rate of growthwould not last as it was due in part to ticket sales for theLondon Olympics and the reversal of negative effects in theprevious quarter from an extra public holiday.

"Stripping out the effects of special events ... suggestsunderlying growth is closer to 0.2-0.3 percent per quarter," thethink tank said.

NIESR says its monthly GDP estimates are usually within0.1-0.2 percentage points of the first estimate of quarterly GDPfrom the Office for National Statistics. The ONS publishes itsfirst estimate of Q3 GDP on Oct. 25.

(Reporting by David Milliken; Editing by Catherine Evans)

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