In afternoon trading in New York, the Dow Jones Industrial Average was up 0.25 per cent, the Standard & Poor's 500 Index gained 0.16 per cent, while the Nasdaq Composite Index advanced 0.31 per cent.
Better-than-expected November sales data for McDonald's lifted its shares 1.3 per cent, following a dismal October during which sales declined for the first time in nine years. Global sales at restaurants open at least 13 months increased 2.4 per cent last month.
"One month does not a trend make ... but it's a nice sign to see them rebound after a horrible October," ITG Investment Research analyst Steve West told Reuters.
Investors are eyeing a two-day meeting by Federal Reserve policy makers starting tomorrow.
In Europe, the Stoxx 600 Index eked out a 0.1 per cent gain from the previous close. It's at the highest level in 18 months, according to Bloomberg. National benchmark stock indexes also rose in London, Paris and Frankfurt.
Italian Prime Minister Mario Monti's unexpected announcement over the weekend that he plans to resign soon after lawmakers approve his budget plan later this month sent the nation's stocks and bonds lower. Italy's FTSE MIB stock index dropped 2.2 per cent, while the yield on the country's 10-year bond was last up 29 basis points at 4.82 per cent.
Elections may be held as early as February - one to two months earlier than expected. European political and financial leaders today pressed for the next Italian government to hold fast on the reforms initiated by Monti. Still, the uncertainty may increase wariness among investors.
"The underlying cracks within the euro zone are actually widening," Georg Grodzki, head of credit research at Legal & General Investment Management in London, told Bloomberg. "Investors will be reading Italian politicians' lips very, very closely."