U.S. stock markets were expected to open a touch firmer on Friday, extending the previous day's gains, although all eyes are on whether Greece could temper sentiment.
The debt-stricken euro zone country was firmly in the spotlight amid mounting concerns that it is close to a default and an exit from the single-currency club.
Euro zone officials are expected to hold an emergency summit Monday after failing to reach an agreement on a cash-for-reforms deal for Greece at a meeting Thursday. Athens has said that without further aid, it will be unable to make a 1.5 billion euro ($1.7 billion) debt payment to the International Monetary Fund on June 30.
Large deposit outflows from Greece meanwhile have raised concerns that Athens may have to implement capital controls.
"In the absence of any major data releases today, the Greece story is likely to dominate once again," Craig Erlam, senior market analyst at currency trading firm OANDA, said in a note.
"It will be very interesting to see whether the jitters kick in as we progress through the session and investors begin to become more risk-averse ahead of such an uncertain weekend," he said.
U.S. stock index futures ticked higher during early London trade, with the Dow Jones industrial average futures up 30 points.
U.S. stocks closed about 1 percent higher on Thursday, with the tech-heavy Nasdaq topping its intraday high from March 2000 as this week's dovish Federal Reserve statement boosted investor sentiment.
The strong performance on Wall Street helped underpin sentiment in Asia, where Japan's Nikkei closed almost 1 percent higher, and in Europe, where shares rose in early Friday trading. However, the Shanghai Composite tumbled 6.4 percent for its worst weekly decline in 7 years with property and banking stocks leading the index lower.
Two Fed officials speak later in the day: San Francisco Fed President John Williams talks on policy at 11:40 a.m. ET, and is the first Fed official to speak after the Wednesday's Fed meeting where the central bank lowered its growth forecasts but said the economy would likely be strong enough to withstand a rate hike this year.
Cleveland Fed President Loretta Mester speaks at 12:45 p.m. on community development and the Fed.