(Adds analyst comment, updates prices, changes dateline)

By Eric Onstad

LONDON, April 1 (Reuters) - Copper prices rose on

Tuesday after four sessions of losses, buoyed by continued

positive data from top metals consumer China, but uncertainty

around U.S. tariffs capped gains.

Benchmark three-month copper on the London Metal

Exchange (LME) added 0.4% to $9,745 per metric ton by 0930 GMT,

rebounding from a level that was its weakest in more than two

weeks touched in the previous session.

Two separate surveys on Monday and Tuesday showed China's

manufacturing sector was expanding more than expected, running

against a tide of weaker activity elsewhere in Asia.

The private sector Caixin/S&P Global manufacturing PMI on

Tuesday showed activity in the world's second-largest economy

picking up, as factories rushed to get goods to customers before

U.S. tariffs took effect.

A day earlier, an official PMI showed manufacturing activity

growing at its quickest rate in a year.

"The PMI data is definitely quite supportive, adding to the

strong momentum coming from China," said Nitesh Shah, commodity

strategist at WisdomTree.

"I do think that China will continue to try to lean against

the wind and provide stimulus for its domestic economy to propel

domestic growth to counteract the loss of potential exports."

Holding back the market, however, was concern about

reciprocal tariffs U.S. President Donald Trump plans to

introduce this week, which he said on Sunday will apply to all

nations.

Copper prices also found support from a shortage of copper

concentrate, which has resulted in negative copper concentrate

processing treatment and refining charges (TC/RCs).

TC/RCs, a key source of revenue for smelters, are a gauge of

availability for copper concentrates. Lower TC/RCs imply tight

supply.

LME tin added 0.3% to $36,745 ton, close to its

strongest since June 2022 hit on Monday due to fears of supply

disruptions from an earthquake in tin-rich Myanmar last Friday.

Among other metals, LME aluminium slipped 0.6% to

$2,519 a ton, zinc eased 0.4% to $2,842, lead lost 0.3%

to $2,007 while nickel gained 1.1% to $16,100.