LONDON (Reuters) - Copper fell on Tuesday as the dollar firmed and uncertainty about Europe's ability to resolve its debt crisis outweighed reports that top metals consumer China will fast-track infrastructure investment.

Three-month copper on the London Metal Exchange touched a week-high of $7,816 a metric ton (1.1 ton) in the session, before erasing gains to $7,712 at 5:37 a.m. EDT (0937 GMT), down 0.2 percent from Monday's $7,731 close.

One of the price supports for copper on Tuesday was a report in the state-backed China Securities Journal that Beijing will fast track its approval of infrastructure investments to combat slowing growth and a sluggish property sector. Copper is used extensively in construction.

Premier Wen Jiabao has also called for additional efforts to support growth, signaling Beijing's willingness to take action after recent data suggested the world's No. 2 economy would slow further in the second quarter.

"I would have thought this would have been more bullish for the market. It shows that sentiment is not terribly bullish at the moment for the metals market," said Standard Chartered analyst Dan Smith.

"You've got one potentially very bullish event set against continued worries about the outlook."

The slowdown in China's economy has weighed particularly hard on the commodities market.

Copper is on track to lose more than 7.5 percent this month, sharply cutting its year-to-date gains to around 2 percent from as much as 15 percent in February.

Falling prices combined with escalating costs that have squeezed cash flow prompted big miners BHP Billiton and Rio Tinto to say they were reconsidering the pace of their long-term expansion plans.

RELUCTANT

Traders are also reluctant to take any strong positions ahead of any resolution for Greece, and the euro zone. Eyes are now on an informal summit of EU leaders in Brussels on Wednesday.

The debt crisis has deteriorated rapidly over the past month, with Greece's potential exit from the 17-country currency bloc no longer taboo. Many economists and policymakers are arguing it would be one of the best ways of restoring market confidence.

A firmer dollar against a basket of currencies also put pressure on copper. A stronger dollar makes commodities priced in the unit more expensive for holders of other currencies.

But overall, copper fundamentals are expected to remain relatively tight over the year ahead, National Australia Bank said in a research note.

"Copper grade degradation, limited new capacity in the horizon and reasonably solid fundamentals for demand should support prices," NAB said.

Tin was $19,325 from $19,250 while zinc, used in galvanizing was $1,895 from $1,905 at Monday's close.

Battery material lead was at $1,930 from $1,941 and aluminum was $2,030 from $2,047. Nickel was $17,017 from $17,185.