* Investors cheer U.S. plan to plow $250 bln into banks
* Index races 1,600 points higher, biggest one-day gain
* Financials, oil and gas groups lead (Adds details)
TORONTO, Oct 14 (Reuters) - The Toronto Stock Exchange's main index made its biggest intraday gain ever at the start of trading on Tuesday as the market played catch-up with Monday's monster surge on Wall Street and welcomed a U.S. plan to inject $250 billion into its banks.
Canadian markets were closed on Monday for Thanksgiving Day.
Shortly after 9:45 a.m. (1345 GMT), the S&P/TSX composite index .GSPTSE was up 1,169.50 points, or 12.90 percent, at 10,234.66. All 10 sectors were higher. Right after the open the index was up a record-breaking 18 percent.
The big jump in the Toronto index came on the heels of big gains on world stock markets on Monday and continuing strength on Tuesday as investor jitters about the stability of the financial system eased.
The U.S. plan to plow $250 billion into its banks, following similar measures in Europe, is designed to get them lending to each other again. [ID:nTRS000084]
The U.S. plan broadly boosted sentiment in commodities as well, with the energy sector up 18 percent.
Imperial Oil (IMO.TO) rose 28.5 percent to C$40.18, while Petro-Canada PCA.TO gained about 25 percent to C$29.45.
$1=$1.15 Canadian Reporting by Ka Yan Ng; Editing by Peter Galloway