Europe's Stoxx 600 Index ended the session with a 0.4 per cent drop from the previous close, while Greece's ASE Index fell 1.8 per cent. France's CAC 40 Index declined 0.2 per cent, while Germany's DAX slid 0.6 per cent.
The UK's FTSE 100 Index advanced 0.2 per cent.
"The optimism we had about getting close to a deal has faded. That doesn't mean we won't get one, but insiders seem less confident than they were a few days ago," Phil Orlando, chief equity market strategist at Federated Investors in New York, told Reuters.
"If Greece defaults, the economic impact on the US will be relatively minor, but the headline risk will be significant and could lead to a drop of 5 or even 10 per cent," Orlando said.
Meanwhile, a report showed German business confidence suffered. The Ifo institute's business climate index fell more than expected, declining to 107.4 in June from 108.5 in May.
In the US, a Commerce Department report showed gross domestic product slid at a 0.2 per cent annual rate in the first quarter. That's less than last month's estimate for a 0.7 per cent contraction. Solid consumer spending helped buoy the outlook.
"These revisions have a marginally positive impact on our view of the second quarter," Nariman Behravesh, chief economist at IHS in Lexington, Massachusetts, told Reuters. "Demand is still solid, but the adjustment to the strong dollar has not run its course."
In late trading in New York, the Dow Jones Industrial Average fell 0.84 per cent, while the Standard & Poor's 500 Index slid 0.56 per cent, and the Nasdaq Composite Index declined 0.58 per cent. Earlier in the session, the Nasdaq climbed to a record 5,164.36.
Slides in shares of DuPont and those of UnitedHealth, down 3.2 per cent and 2.4 per cent respectively, led the Dow lower.
Oil weakened. A government report showed US crude oil inventories fell last week, but petrol stockpiles unexpectedly surged.
The importance of US oil output was confirmed by the Organisation of Petroleum Exporting Countries, which noted in an annual statistical bulletin that the group's share of the global market slipped to 41.8 per cent in 2014, the lowest since 2003.