(Updates with Wall Street outlook, fresh prices)
By Natsuko Waki
LONDON, Feb 25 (Reuters) - World stocks and the dollar rose on Monday as talk of a rescue plan for U.S. bond insurer Ambac and comments that Qatar is interested in investing in European banks eased concerns about the health of the banking sector.
Commodity prices remained firm, with U.S wheat and soybean prices setting record highs due to supply concerns. Silver hit a 27-year high and platinum and gold held near last week's record peaks. High commodity prices have been a source of inflation concerns in recent weeks.
Investors have been spooked by the threat of credit downgrades raised by the monoline bond insurers' exposure to U.S. subprime mortgages.
The monolines provide cover against defaults in securitised debt. Downgrades could trigger a wave of forced selling in bonds the insurers have guaranteed, which would lead to more losses by banks in the six-month-old credit crunch.
A rescue plan for Ambac Financial <ABK.N>, which could be announced on Monday or Tuesday, could allow the U.S. bond insurer to keep its top rating and avert debt sell-offs. (For story click on [
])"We had some positive news on Ambac -- the fact that certainly one of the largest monolines could be underwritten by a consortium of banks," said Richard Hunter, head of UK equities at Hargreaves Lansdown.
"That's taken very positively because the market is looking for signs perhaps some of the corners have been turned."
The FTSEurofirst 300 index <
> rose 1.3 percent while MSCI main world equity index <.MIWD00000PUS> was up 0.7 percent.U.S. stock futures were up around 0.1 percent, indicating a firmer open on Wall Street <SPc1>.
Credit market sentiment also improved in Europe. The iTraxx Crossover index <ITCRS5EA=GFI>, the most widely watched indicator for European credit market sentiment, narrowed to 545 basis points, indicating the cost of corporate debt insurance has eased after hitting all-time peaks last week.
The dollar was up 0.2 percent against a basket of six major currencies <.DXY>, capitalising on optimism surrounding the U.S. bond insurers.
Banks and insurers were the main gainers in Europe, with both sectors <.SX7P> <.SXIP> up nearly 3 percent after Qatari prime minister Sheikh Hamad bin Jassim al-Thani's comments.
Al-Thani, who heads the country's $60 billion sovereign wealth fund, told Reuters on Saturday that Qatar is looking to spend $10-15 billion over the next two years on bank shares and he favoured investing European over U.S. lenders.
Britain's Sunday Telegraph newspaper reported that Qatar is considering making an investment into the UK's second largest bank, the Royal Bank of Scotland <RBS.L>. The Gulf state already has a less than 2 percent stake in Credit Suisse <CSGN.VX>.
State-run investment vehicles, which actively invest the country's national wealth, have been a crucial provider of liquidity in the financial market over the past year as they buy stakes in U.S. and European banks hit by the credit crunch.
COMMODITIES AND INFLATION
Firmer food and commodity prices have been threatening to push inflation higher in developed economies, complicating the job of some central banks which are keen to cut interest rates to limit the effect of the credit crisis on the real economy.
On Monday U.S. spring wheat on the Minneapolis Grain Exchange hit a record above $20 per bushel, while European wheat prices rose more than 2 percent.
Chicago soybean futures <0#S:> and European rapeseed also hit record peaks, driven by Chinese demand.
"The problem for the Fed and many other central banks is that inflation concerns will limit the extent of possible monetary easing to help counteract weakness in growth," Mitul Kotecha, head of global FX research at Calyon, said in a note.
"The market will continue to grapple with growth concerns on the one hand and inflation pressures on the other."
U.S. light crude oil <CLc1> was down 0.1 percent at $98.68 a barrel, although the downside was limited by geopolitical concerns in Iran and Turkey. Silver <XAG=> rose as high as $18.10 an ounce while gold <XAU=> rose to $951.90 an ounce.
Emerging market assets were firm, with emerging sovereign spreads <11EMJ> tightening 5 basis points while emerging stocks <.MSCIEF> rising 0.8 percent.
The March Bund future <FGBLH8> was down 39 ticks.
(Additional reporting by Dominic Lau)