Stock index futures extended their losses early on Monday, mirroring a selloff in Asian and European stocks on mounting worries the equities' recent surge had run ahead of the global economic recovery.

At 4:18 a.m. EDT, futures for the S&P 500 were down 1.92 percent, Dow Jones futures were down 2.11 percent and Nasdaq 100 futures were down 2.11 percent.

Chinese stocks <.SSEC> sank 5.8 percent to their lowest close in two months on Monday on worries about added share supplies and commodity price declines, while Japan's Nikkei average <.N225> fell 3.1 percent as investors locked in profits after gross domestic product data failed to produce a positive surprise.

European stocks <.FTEU3> were down 1.8 percent in a broad selloff in morning trade.

(Reporting by Blaise Robinson in Paris and Dominic Lau in London)