McDonald's

(MCD) - Get Report

is fending off the barbarians at its golden arches with the success of its breakfast menu and its new Snack Wrap.

The fast-food giant said Thursday that its same-store sales, or sales at stores open at least a year, rose at a 7.7% clip in September. On the basis of the results, the company forecast third-quarter earnings above Wall Street's expectations.

The burger empire estimated preliminary third-quarter earnings of 68 cents a share, including one penny a share for impairment and other charges. Analysts, on average, were expecting earnings of 63 cents a share, according to Thomson First Call.

McDonald's said its systemwide sales for its namesake restaurants worldwide increased 9.8% in September, or 8.7% in constant currencies. For the quarter, systemwide sales rose 8.4%, or 6.9% in constant currencies.

The performance may pose an obstacle for the plans of shareholder activist Bill Ackman, a hedge fund manager with Pershing Square Capital who is reportedly

buying up shares of McDonald's and planning to wage a proxy fight against the company's management.

In the U.S., McDonald's same-store sales, or comps, rose 7.1% for September and 4.1% for the quarter. In Europe, its comps gained 9% for the month and 7.6% for the quarter, thanks to particularly strong sales in the U.K., Germany and France. In Asia, the Middle East and Africa, comps were up 6.6% for September and 6.1% for the quarter, primarily driven by Japan's performance.

"Our Plan to Win is powering sustainable momentum in our business with every area of the world once again posting strong comparable sales growth," said McDonald's in a press release. "We are increasing relevance, enhancing menu variety and improving customer convenience."

Ackman, who last year emerged as a major agitator at McDonald's, has plans to buy $2 billion worth of the company's shares, and he has sent a letter to shareholders in an attempt to garner support for a proxy fight, according to a recent report from

Bloomberg News

.

Ackman couldn't be immediately reached to comment on McDonald's results or his plans for the company.

Shares of McDonald's recently were up 80 cents, or 2%, to $42.05 in premarket trading.