* STOXX 600 ends little changed
* FTSE rises as Brexit fears hit pound
* Dechra falls with 'Hard Brexit' contingency plan
* Belgium's Ontex sinks after rejecting offer (For live blogs on the European and U.S. stock markets, type LIVE/ in an Eikon news window)
By Julien Ponthus
LONDON, Sept 3 (Reuters) - European shares ended little changed on Monday as worries about U.S. trade policy and concern over emerging markets weighed on stocks after Asian markets closed lower.
The pan-European STOXX 600 index gained 0.05 percent to 382.46 points. Activity was subdued as U.S. markets were closed for Labor Day.
Stocks in Europe showed little reaction to a report that euro zone manufacturing growth had declined to its slowest pace in nearly two years.
London's FTSE 100 was the only trading centre in the black, ending up 0.8 percent. A weaker pound provided an accounting boost for British blue chips.
"With the U.S. off for Labor Day there was little change to the European markets, the start to September (was) defined by sterling's slide," said Connor Campbell, an analyst for Spreadex.
Italian banks gained despite the rating agency Fitch reducing its outlook for Italy to negative on Friday.
The biggest mover was veterinary products group Dechra Pharmaceutical, which sank 21.4 percent after publishing its full-year results and saying it was implementing a "hard Brexit" mitigation plan.
"What may be concerning the market are references to contingency plans for a ‘hard Brexit’ and the fact an increasing number of distributors are focusing on the sale and marketing of their own products," said AJ Bell investment director Russ Mould.
Belgian diaper manufacturer Ontex fell 19.5 percent after rejecting a proposed cash offer for its outstanding shares from the private equity firm PAI Partners, saying it undervalued the company.
The best performance was posted by the Dutch offshore energy company SMB, which rose 10.7 percent after announcing that it had reached a settlement in Brazil over alleged improper sales practices.
In France, the retailer Casino rose as much as 4 percent after confirming its 2018 targets, only to reverse course and end down 3 percent. Casino's shares fell 10 percent on Friday amid concern over its debt, and it has been targeted by U.S. short seller Muddy Waters.
Drug maker Sanofi gained 1.1 percent after securing approval in Europe for a blood clotting disorder treatment using nanobodies. (Additional reporting by Danilo Masoni; Editing by Larry King)