The Toronto stock market headed for a slightly higher open Tuesday as German Chancellor Angela Merkel downplayed a possible downgrade of the credit rating of 15 eurozone countries, including Germany’s, by ratings agency Standard & Poor’s.

Merkel said that she expected a meeting of European leaders later this week in Brussels would help restore markets’ confidence.

Meanwhile, traders took in the last of the earnings reports from the big five banks.

Bank of Montreal (TSX:BMO) reported that its quarterly profit rose 21% to $897 million. Results were helped along by the acquisition of Wisconsin-based Marshall & Ilsley. On an adjusted basis, profit was $1.27 a share, four cents less than analysts had expected, according to Thomson Reuters.

The Canadian dollar moved slightly lower ahead of the Bank of Canada’s scheduled announcement on interest rates, which was due to be released at 9 a.m. EST. The loonie was off 0.1 of a cent to 98.25 cents US.

U.S. futures advanced with the Dow Jones industrial futures ahead 42 points to 12,108, the Nasdaq futures were up 10.75 points to 2,335.75 and the S&P 500 futures rose 3.3 points to 1,258.3.

The S&P announcement came just hours after Merkel and French President Nicolas Sarkozy urged changes to the European Union treaty that would centralize decision-making on spending and borrowing for the 17 countries that use the euro.

The proposal is set to form the basis of discussions at the EU summit in Brussels on Friday.

Tighter political and economic coordination among euro countries is seen as a precursor to further financial aid from the European Central Bank, the International Monetary Fund, or some combination.

But a tighter union would likely also result in heavier financial burdens for the region’s stronger economies, which have already put up billions of euros to rescue Greece, Ireland and Portugal.

S&P said its decision was “prompted by our belief that systemic stresses in the eurozone have risen in recent weeks to the extent that they now put downward pressure on the credit standing of the eurozone as a whole.”

Stock indexes in Toronto and New York finished higher Monday on optimism that the EU summit would yield a lasting fix for Europe’s debt crisis with the TSX up 44 points and the Dow up 78 points.

Markets have been jittery because of fears that the euro might disintegrate, causing a sharp recession in Europe that would spread through the world economy. But investors have felt more optimistic in recent days on the conviction that eurozone leaders are finally serious about settling the debt crisis once and for all.

Commodity prices were mixed with the January crude contract on the New York Mercantile Exchange up a dime to US$101.09.

Copper prices were lower with the March contract on the Nymex down six cents to US$3.55. News that China was easing lending in order to encourage growth pushed copper prices up almost 10% last week. China is the world’s biggest consumer of the metal.

Bullion prices also headed lower with the February contract down $13 to US$1,721.50 an ounce.

European markets were mixed with London’s FTSE 100 index moved up 0.18%, Frankfurt’s DAX lost 0.8% and the Paris CAC 40 was down 0.31%.

The S&P announcement pushed stocks earlier in Asia.

Japan’s Nikkei 225 dropped 1.4%, South Korea’s Kospi fell one per cent, Hong Kong’s Hang Seng lost 1.2% and Australia’s S&P/ASX 200 shed 1.4%.

In other corporate news, Precision Drilling Corp. (TSX:PD) announced that it will take a charge of up to $120 million in the fourth quarter on the decommissioning of 36 drilling rigs and 13 service rigs.