MANILA, May 2 (Reuters) - London copper futures recovered from their weakest level in nearly a month on Wednesday after a private survey showed growth in China's manufacturing sector unexpectedly picked up in April, brightening the demand outlook in the top user of the metal. Three-month copper on the London Metal Exchange was up 1.2 percent at $6,829 per tonne by 0213 GMT, after hitting a low of $6,710 on Tuesday, its weakest since April 4. The Caixin/Markit Manufacturing Purchasing Managers' index (PMI) climbed to 51.1 in April from a four-month low of 51.0 in March, and topped economists' forecast for a modest slowdown to 50.9. But the same survey showed a sub-index on export orders shrinking for the first time since November 2016. An official PMI survey on Monday also showed slower shipment orders last month. The data "reflects a deteriorating export market and strengthened domestic consumption" that may cancel each other out and keep gross domestic product growing at 6.5 percent this year as Beijing had forecast, said Helen Lau, analyst at Argonaut Securities. "For the rest of the year, as the export situation may deteriorate, fiscal stimulus and further monetary easing will likely take place so as to protect the 6.5 percent growth target, which in turn will underpin growth for commodity demand," Lau said in a note. SHANGHAI COPPER: The most-traded June copper contract on the Shanghai Futures Exchange slid 1.2 percent to 50,990 yuan ($8,022) a tonne, tracking losses in London in the prior session as Chinese markets reopened after a two-day public holiday. FEDERAL RESERVE: Investors are also awaiting the statement from the U.S. Federal Reserve when its two-day policy meeting concludes later on Wednesday. While the Fed is widely expected to keep the benchmark interest rate on hold, it looks certain to raise it again next month, given signs of possible acceleration in the U.S. economy. U.S. DATA: Investors are also focused on Friday's employment report for April for further indications of the strength of the U.S. economy and inflation pressures. Data on Tuesday showed U.S. factory activity slowed for a second straight month in April. U.S. RESTRICTIONS: U.S. officials are pushing for quotas and "other restrictions" on steel and aluminium imports, a top trade official said after the White House announced a month-long extension of tariff exemptions for Canada, Mexico and the European Union. RUSAL: The U.S. Treasury gave investors an additional month to divest or transfer their holdings in sanctions targets major aluminium producer United Company Rusal Plc, En+ Group Plc and GAZ Group. ALUMINIUM: LME aluminium eased 0.4 percent to $2,250.50 a tonne while its Shanghai counterpart was off 0.2 percent at 14,450 yuan. OTHER METALS: LME nickel rose 1.8 percent to $13,900 a tonne and zinc climbed 1.2 percent to $3,089.50. In Shanghai, nickel eased 0.4 percent to 103,890 yuan per tonne and zinc dropped 0.5 percent to 23,735 yuan. MARKETS: The dollar held near a four-month high against a basket of major currencies, buoyed by the outlook for a strong U.S. economy and rising yields amid signs of slowdown elsewhere, especially in Europe. Asian shares were steady.