MELBOURNE, March 22 (Reuters) - London copper climbed off its lowest in three months on Thursday after the U.S. Federal Reserve signalled a slower pace of rate rises this year, which weighed on the dollar. "Post the FED rate hike and forward guidance on an additional two hikes, the market found reason to re-assert the bearish USD theme and this in turn has boosted the USD denominated commodities markets," said Marex Spectron in a report. "The positive short-term technical picture across the LME complex combined with the USD weakness should inspire further short-covering today with room to run on some of these metals given their positioning." FUNDAMENTALS * COPPER: London Metal Exchange copper traded up 0.5 percent at $6,830 a tonne by 0725 GMT, extending a small recovery from the previous session, when prices plumbed a three-month trough at $6702 but finished up half a percent. Shanghai Futures Exchange copper rose 0.8 percent. * FEDERAL RESERVE: The U.S. Federal Reserve raised interest rates on Wednesday and forecast two more hikes for 2018 in its first policy meeting under new Fed Chairman Jerome Powell. * DOLLAR: The U.S. dollar was on the defensive on Thursday after posting its largest loss in two months when the Federal Reserve turned out to be less hawkish than anticipated. * TARIFFS: President Donald Trump will announce tariffs on Chinese imports on Thursday, a White House official said, in a move aimed at curbing theft of U.S. technology and likely to trigger retaliation from Beijing and stoke fears of a global trade war. * CHINA: China accused the United States of "repeatedly abusing" trade practices, as Beijing braced on Thursday for an imminent announcement from U.S. President Donald Trump slapping more tariffs on Chinese imports. * RIO TINTO: Swiss prosecutors confirmed on Wednesday they were investigating whether miner Rio Tinto paid bribes linked to the landmark Oyu Tolgoi copper-gold mine. * ALUMINIUM: Among other metals, LME aluminium pared more than 1 percent gains to $2,094, still up 0.6 percent, having broken back above the 200-day moving average after closing below the key technical level for two sessions in a row. * Shfe aluminium however was flirting with its weakest levels in 14 months, around 13,820 yuan, with more China production expected to come on stream in coming weeks after the expiration of the country's winter pollution controls. * Shfe lead rallied more than 3 percent, partly due to a technical breakout based on gains in sister-metal zinc, where available exchange-based inventories have dwindled.