The Shanghai Composite got a further boost on Monday, after the Chinese government announced market reforms that could increase market liquidity. It has proposed opening up its stock and bond markets, as well as relaxing foreign ownership of companies and pursuing both inward and outward investment.
U.S. Treasury Secretary Jacob Lew will travel to China on Monday to discuss the pace of reforms with the Chinese government, and also the yuan currency.
The dollar declined against the currencies of major U.S. trading partners, while the 10-year Treasury yield added 1 basis point to 2.638 percent.
Gold futures for June delivery rose $9.30, or 0.7 percent, to $1,296.90 an ounce; crude-oil futures for June delivery climbed 49 cents, or 0.5 percent, to $100.48 a barrel.
In the corporate space this week, investors will focus on Pfizer's ongoing attempts to acquire U.K. rival AstraZeneca. Pfizer boss Ian Read will appear before a U.K. business select committee on Tuesday alongside AstraZeneca's Pascal Soriot.
First-quarter retail earnings begin in earnest this week, with results due from Wal-Mart, Macy's and JC Penney. However, Concho Resources and Gogo are the only companies of note posting numbers before markets open on Monday.
Europe market gains were capped on Monday by concerns in Ukraine. In the eastern city of Donetsk, 89 percent of the populace is said to have voted in favor of seceding from Ukraine on Sunday. The West is concerned the referendum could be a prelude to annexation by Russia, as occurred in Crimea in March after a different secession vote. Europe foreign ministers will meet in Brussels on Monday to mull tighter sanctions against Russia.