* Polls show "In" gaining momentum before referendum
* Sterling rises strongly, safe-haven yen falls
* Low-risk debt yields rise, gold drops as safety bid eases
* Brent crude tops $50 a barrel on reduced Brexit fear (Updates with early U.S. market activity, changes dateline, previous LONDON)
By Edward Krudy
NEW YORK, June 20 (Reuters) - Global stock indexes jumped on Monday and sterling rebounded broadly after polls showed support for Britain staying in the EU strengthened before Thursday's referendum.
At the start of what could be a frenetic weak for global markets, safe-haven assets such as the yen and gold retreated. Monday's surge in equity markets saw Wall Street recover losses from last week, when the chances of the United Kingdom leaving the EU, or "Brexit", appeared to be gaining momentum.
The surge in sterling, which rose more than 2 percent against the dollar, coincided with a broad retreat in the green back as several polls showed the "Leave" campaign weakening. Markets will likely remain volatile and headline-driven in the run-up to the vote, which still appears too close to call.
"Everyone is going to hold their breath until Thursday or Friday, when we get to know the result," said Adam Hewison, chief executive of Ino.com in Maryland.
The MSCI's all-country world stock index .MIWD00000PUS surged 2.1 percent, while Wall Street stocks as measured by the S&P 500 .SPX jumped 1.2 percent, their strongest daily increase in nearly three weeks. polls showed "In" regaining the lead and another showed the "Out" campaign's lead narrowing, though the overall picture was of an evenly-split electorate. Bookmakers' odds have shown those wishing to stay in the EU ahead, and Betfair put the implied probability of a vote to "Remain" at 72 percent on Monday, up from 60-67 percent on Friday. Treasury yields rose as traders trimmed safe-haven holdings of lower-risk government debt. Benchmark 10-year Treasury yield US10YT=RR rose over 5 basis points from late Friday to 1.675 percent after reaching 1.680 percent earlier Monday. ID:nL1N19C0KK
The "risk on" move was more pronounced in Europe. The pan-European FTSEurofirst 300 index .FTEU3 added 3.7 percent, led by a 4.3 percent rise in banks .SX7P , while Britain's blue-chip FTSE 100 index .FTSE chalked up a 3.1-percent gain.
Sterling rose as far as $1.4707 and was last up 2.4 percent at $1.4693 GBP= , having hit a two-week low of $1.4013 on Thursday. It soared 2.7 percent to 153.53 yen GBPJPY= and 1.9 percent against the euro to 77.08 pence EURGBP= .
EURO GAINS AS BREXIT WORRIES EASE
The euro, which has also suffered due to "Brexit" worries, strengthened 0.5 percent to $1.1329 EUR= , after rising as far as $1.1382.
The yen, often sought by investors in times of market tension, fell 0.4 percent to 104.45 per dollar JPY= . The dollar fell 0.7 percent against a basket of currencies .DXY .
German 10-year government debt DE10YT=TWEB yielded 0.063 percent, up from a record low of minus 0.037 percent on Thursday. prices, which have also been under pressure, extended Friday's gains. Brent crude LCOc1 topped $50 a barrel for the first time since June 14. It last traded at $50.42, up $1.24 on the day. XAU= , another safety play, fell 1.1 percent to just below $1,285 an ounce. It rose 1.5 percent on Friday for its biggest single-day gain since June 3.
<^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Reuters' new Live Markets blog on European and UK stock markets
reuters://realtime/verb=Open/url=http://emea1.apps.cp.extranet.thomsonreuters.biz/cms/?pageId=livemarkets Interactive Brexit graphic
http://tmsnrt.rs/1Ke31HF Asset performance in 2016
http://reut.rs/1WAiOSC Currencies in 2016
http://link.reuters.com/tak27s
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