* Copper down 1.6 percent at $5,712 a tonne
* Weaker dollar could yet provide price support
* Nickel falls as supply worries recede (Adds official prices)
By Pratima Desai
LONDON, March 27 (Reuters) - Copper prices slid on Monday as funds cut bets on higher prices after U.S. President Donald Trump's failure to push through healthcare reform fuelled concern about his ability to implement his economic policies.
Benchmark copper on the London Metal Exchange traded down 1.9 percent at $5,694 a tonne in official rings.
"Trump's election was seen as good for markets, but he is now being seen as potentially less effective than people were thinking," said SP Angel analyst John Meyer.
"His failure on Obamacare has created uncertainty about whether he can push his policies through Congress."
* U.S. HEALTHCARE: Trump suffered a political setback on Friday in a Congress controlled by his own party when Republican leaders pulled legislation to overhaul the U.S. healthcare system.
* DOLLAR: A weaker dollar, at four-month lows against a basket of currencies, could yet support prices because it makes dollar-denominated metals cheaper for holders of other currencies.
* TECHNICALS: A closing copper price below the 100-day moving average around $5,749 could prompt further losses.
* ESCONDIDA: The union at Chile's Escondida copper mine has ended its 43-day strike by invoking a legal provision to extend workers' old contract by 18 months, leaving owner BHP Billiton in a weaker position for future negotiations. * ZINC: The market focus is on New Orleans, warehouses' on-warrant stocks have dropped to 183,800 tonnes after a further 21,300 tonnes of cancellations or metal earmarked for delivery. MZNSTX-TOTAL On-warrant zinc stocks -- metal available to the market -- have fallen 42 percent this year to the lowest levels since November 2008.
* VEDANTA: Indian mining company Vedanta Resources said on Friday that it will invest $1 billion in its Zambian mining unit Konkola Copper Mines (KCM).
* NICKEL: Receding worries about supply shortages pushed nickel down 1.3 percent to $9,745 a tonne, having touched $9,655, its lowest since Jan. 30.
* OTHER METALS: Aluminium was down 0.8 percent at $1,924 a tonne, zinc ceded 1.9 percent to $2,776, lead lost 1.5 percent to $2,317 and tin slid 1.7 percent to $19,515 a tonne.
* LME/SHFE ARBITRAGE: LME copper trading was at a 511 yuan premium to prices on the Shanghai Futures Exchange at 1307 GMT, aluminium was at 1,696 yuan discount, zinc a 58 yuan premium, lead at a 1,386 yuan discount and nickel at a 2,679 yuan premium.
Three month LME copper
Most active ShFE copper
Three month LME aluminium
Most active ShFE aluminium
Three month LME zinc
Most active ShFE zinc
Three month LME lead
Most active ShFE lead
Three month LME nickel
Most active ShFE nickel
Three month LME tin
Most active ShFE tin
Editing by David Goodman and Louise Heavens