* TSX down 65.99 points, or 0.42 percent, to 15,481.76
* Nine of the TSX's 10 main groups were down
TORONTO, April 3 (Reuters) - Canada's main stock index was broadly lower late morning on Monday, reversing earlier gains as a retreat led by financial stocks offset advances by mining stocks.
The financials group slipped 0.8 percent, as six of the 10 most influential decliners were banks and insurers. Royal Bank of Canada was down 0.9 percent at C$96.02, while Sun Life Financial fell 1.8 percent to C$47.68.
Enbridge Inc, another influential decliner, fell 1.3 percent to C$54.99. The energy group, which retreated 0.7 percent, tracked oil prices which were pressured by a rebound in Libyan oil output. U.S. crude prices were down 0.7 percent to $50.25 a barrel, while Brent crude lost 0.6 percent to $53.19.
Magna International Inc also dragged on the index, sliding 2.8 percent to C$55.81, helping push the consumer discretionary group down 0.5 percent.
At 10:59 a.m. ET (1459 GMT), the Toronto Stock Exchange's S&P/TSX composite index fell 65.99 points, or 0.42 percent, to 15,481.76. All but one of the index's 10 main groups were in the red. The index mirrored moves lower on Wall Street.
Teck Resources Ltd was up 4 percent to C$30.25, as thermal coal prices and European coal futures climbed. Prices rose due to a disruption of coal exports caused by rail line damage in northeast Australia from Cyclone Debbie, which struck last week.
Gold miners including Barrick Gold Corp, which advanced 1.6 percent to C$25.67, and Franco Nevada Corp , which climbed 1.6 percent to C$88.52, helped give the overall materials group a 1.1 percent boost.
In economic data, Canadian business were more optimistic about future sales and exports, and plan to boost hiring and investment to meet demand despite uncertainty about U.S. protectionism, according to the Bank of Canada's quarterly business outlook survey.
Declining issues outnumbered advancing ones on the TSX by 143 to 98, for a 1.46-to-1 ratio on the downside.
The index was posting 5 new 52-week highs and no new lows. (Reporting by Solarina Ho; Editing by David Gregorio)