The Toronto Stock Exchange appeared headed for a lower open as commodities slipped amid uncertainty about a tentative deal to resolve Greece’s debt crisis ahead of a summit of European leaders.

The Canadian dollar lost 0.43 of a cent to 99.50 cents US.

The February gold contract fell US$9.10 to $1,723.10 per ounce, and the March oil contract shed 41 cents to $99.15 per barrel. Copper prices were down six cents at US$3.83.

Wall Street was also set for a lower open with the Dow Jones industrial futures down 75 points to 12,541. The broader S&P 500 futures were down 8.7 points to 1,303.8. The Nasdaq futures were 16 points lower at 2,440.

European leaders are gathering in Brussels hope to focus on how to stimulate economic growth when huge government spending cuts threaten to push many countries back into recession.

The latest data showed Spain’s economy shrank in the last three months of 2011.

Greece has reached a tentative deal with its private creditors that could avert a disastrous default this spring. Investors holding €206 billion ($272 billion) in Greek bonds would exchange them for bonds with half the face value. The replacement bonds would have a longer maturity and pay a lower interest rate. When the bonds mature, Greece would have to pay its bondholders only €103 billion.

But because Greece has been in recession for years, some experts fear it could need more rescue loans from its bailout partners — other eurozone countries and the International Monetary Fund — if it is to remain solvent.

European markets also declined. Britain’s FTSE lost 0.84%, France’s CAC slid one per cent and Germany’s DAX was down 0.78%.

In Asia, most indexes fell as investors reacted to Friday’s release of data showing the U.S. economy grew more slowly than expected in the fourth quarter.

In Canadian corporate news, Valeant Pharmaceuticals International Inc. (TSX:VRX) withdrew its offer for Irvine, Calif.-based ISTA Pharmaceuticals Inc. of US$7.50 per share due to a “lack of progress.”

Specialty paper producer Catalyst Paper Corp. (TSX:CTL) says that one of the unions at its Crofton mill in B.C. has rejected a new contract that must be ratified as part of the company’s new refinancing plan to stay alive.

RuggedCom Inc. (TSX:RCM), a maker of computers and networks for rugged applications, says it has found a white knight bidder to top a hostile takeover offer from St. Louis-based Belden Inc. The Canadian company announced early Monday it has struck a deal with Siemens Canada Ltd. to sell the company for $33 a share, or about $382 million.