* Macro data improving but inventory levels worry

* Strikes lend support to cap copper losses

* U.S. weekly jobless claims fall more than expected (Changes headline, adds NEW YORK to dateline, recasts, updates with New York copper prices, adds analyst comments)

By Chris Kelly and Maytaal Angel

NEW YORK/LONDON, Nov 12 (Reuters) - Copper prices ended lower on Thursday, weighed down by a slight rebound in the U.S. dollar and growing concerns about demand weakness after London stockpile levels broke above 400,000 tonnes.

Nickel MNI3 inventories on the London Metal Exchange (LME) rose above 131,700 tonnes, the highest since early 1995, driving prices of the metal down more than 5 percent to their lowest since late July.

Copper for December delivery HGZ9 on the New York Mercantile Exchange's COMEX division shed 1.85 cents to end at $2.9475 a lb, near the lower end of its $2.93 to $3.0010 session range.

LME copper for three-month delivery MCU3 finished down $37 at $6,503 a tonne from $6,540 at the close on Wednesday and compared with a session low at $6,468.

John Gross, publisher of the Copper Journal, said that despite the bearish fundamental backdrop in the copper market, prices remained locked in a higher trend.