* Break below $1,497/oz could trigger fall to $1,453 -technicals
* Speculators raise bullish COMEX gold, silver bets -CFTC
* Silver falls to lowest in nearly two weeks
By Asha Sistla
Sept 9 (Reuters) - Gold fell to an over two-week low on Monday, briefly breaking below the key $1,500 support, as renewed risk appetite and gaining U.S. yields outweighed support for bullion from expectations for interest rate reductions by top central banks.
Spot gold XAU= fell 0.2% to $1,503.56 per ounce at 1:36 p.m. EDT (1736 GMT). The metal touched $1,497.30, its lowest since Aug. 23.
U.S. gold futures GCv1 settled down 0.3% to $1,511.10.
Higher U.S. Treasury yields and a "bit of a renewed risk appetite" are weighing on gold, said Bart Melek, head of commodity strategies at TD Securities in Toronto.
"Gold positions are extremely long right now so its not particularly surprising that we're seeing some profit-taking and extension of short exposures right now. ... The market got a little bit ahead and it's paring back that attitude."
Speculators increased their bullish positions in COMEX gold and silver contracts in the week to Sept. 3, the U.S. Commodity Futures Trading Commission (CFTC) said on Friday. CFTC/
U.S. Treasury yields rose while stock markets gained on expectations that global central banks will launch stimulus measures to support their economies. US/ MKTS/GLOB
Risk sentiment was also lifted on Friday after China said it would slash the amount of cash that banks must hold as reserves, while U.S. Federal Reserve Chair Jerome Powell said the central bank would continue to "act as appropriate" to sustain economic expansion. see a high chance of a quarter percentage point cut to interest rates in the Fed's September policy meeting FEDWATCH . The European Central Bank is also expected to cut rates later this week.
On the flip side, analysts said the lower interest rates would keep gold supported.
Lower interest rates decreases the opportunity cost of holding non-yielding bullion and weigh on the dollar, making gold cheaper for investors holding other currencies.
Meanwhile, the dollar .DXY eased against a basket of major currencies. USD/
"Across the world, you have so much negative rates, which is a big catalyst for gold and that's not going away anytime soon," said Michael Matousek, head trader at U.S. Global Investors.
Spot gold is expected to test technical support at $1,497 per ounce. A break below that could cause a further fall to $1,453, according to Reuters technical analyst Wang Tao. XAG= shed 0.5% to $18.08 per ounce, after falling to a near two-week low of $17.89 in the session.
Palladium XPD= was up 0.4% at $1,542.95 per ounce after hitting $1,562.27, while platinum XPT= remained unchanged at $949.81.