NEW YORK (TheStreet) -- Stock futures were set to open significantly lower as global markets tumbled in a continued bond selloff. 

S&P 500 futures were down 0.69%, Dow Jones Industrial Average futures fell 0.72%, and Nasdaq futures slid 0.81%. 

U.S. bond yields on Monday hit their highest level since early December. The yield on the 10-year Treasury note climbed to 2.267% during the session.

European markets were trading heavily in the red, pressured by the bond selloff. Germany's DAX was down more than 2%, while France's CAC 40 fell 1.4% and the FTSE 100 in London tumbled 1.7%. 

"It's a matter of concern for the market," Ian Richards, global head of equities strategy at Exane BNP Paribas, told Reuters. "When any particular asset class goes through periods of extreme volatility in a short space of time, people feel the pressure to take their risk exposure lower."

Global bonds have endured a rocky week as a number of macro forces have come to a head: crude oil has hovered around $60 a barrel, the eurozone has increased its inflation expectations as fresh stimulus enters the market, and Greek debt talks appear to be inching along at an agonizing pace. 

AOL (AOL) shares rocketed nearly 20% higher in premarket trading after Verizon (VZ) - Get Report agreed to buy the company for $50 a share. The deal is valued at a total $4.4 billion. 

Lumber Liquidators (LL) - Get Report slipped on reports the embattled company is being denied coverage by its insurers. The flooring company has been hit with lawsuits over the safety of its products.