TORONTO (Bloomberg) — Canada's main stock index rose, led by energy and mining stocks, as oil and nickel prices rose. Royal Bank of Canada shares fell the most since August 2004 after the company's earnings missed analysts' estimates.Imperial Oil, Canada's largest oil company, rose 28 cents to C$50.08 in Toronto. Petro-Canada, the country's third-largest oil company, climbed 28 cents to C$54.69.

Crude oil for July delivery gained $1.02, or 1.6 percent, to $65.20 a barrel in New York, after oil workers were seized off the coast of Nigeria's Niger Delta. Gasoline futures rose 2 percent yesterday on speculation U.S. companies will have to produce more fuel to meet demand from summer drivers.

" There were a number of oil workers kidnapped and futures are a little bit up," said Fred Ketchen, director of equity trading at Scotia McLeod Inc. in Toronto. "If we're flat at the end of the day after yesterday's fairly substantial sell-off, that's gotta be a win."

The Standard & Poor's TSX Composite Index fell on Thursday for the first time since May 14, dropping 196.24, or 1.4 percent, to 13,946.27 in Toronto. Yesterday's sell-off erased gains made by the index on Tuesday and Wednesday, and left the TSX with its first weekly decline in four weeks.

The index rose 77.80, or 0.6 percent, to 14,024.07 on Friday.

The gasoline futures had jumped after Valero Energy and ConocoPhillips cut production in Louisiana and Texas. In Nigeria, workers at Nigerian National Petroleum Co. began the second day of a strike that stalled operations at export terminals.

Three Americans and four Britons were among a group of oil workers kidnapped from a pipe-laying vessel off the coast of the Niger Delta in Nigeria today, according to US and UK government spokesmen. Sabotage and kidnappings in the oil-rich delta region of Nigeria, Africa's biggest producer, have surged following last month's presidential elections.