Europe's Stoxx 600 Index finished the day with a 0.2 per cent decline from the previous close. Greece's ASE Index rose 0.1 per cent. France's CAC 40 Index slipped 0.1 per cent, while the UK's FTSE 100 Index fell 0.5 per cent. Germany's DAX eked out a 0.02 per cent gain.
Germany's 10-year bund yield rose two basis points to 0.86 per cent, after earlier in the day falling as low as 0.82 per cent and rising as high as 0.89 per cent.
"Most people are sidelined and waiting to see if we get the deal everyone hopes for," Allan von Mehren, chief analyst at Danske Bank in Copenhagen, told Bloomberg. "Most investors do expect a deal but it's probably going to be a last-minute one. Until then there will be ups and downs - there's still some time left to bite their nails."
In late trading in New York, the Dow Jones Industrial Average fell 0.38 per cent, while the Standard & Poor's 500 Index slipped 0.20 per cent, and the Nasdaq Composite Index shed 0.26 per cent.
Slides in shares of Caterpillar and those of Nike, down 1.5 per cent and 1 per cent respectively, led the Dow lower. Bucking the trend were shares of UnitedHealth, last 2.4 per cent higher, amid consolidation in the industry and after the US Supreme Court affirmed the longer-term outlook for President Barack Obama's Affordable Care Act.
Health insurer Aetna is closing in on an acquisition of Humana and could reach a deal as early as this weekend, Bloomberg reported, citing several people with knowledge of the matter. Humana has also received an offer from Cigna but Humana's board prefers the offer from Aetna.
Shares of Aetna last traded 3.2 per cent higher, while those of Humana were 6.7 per cent stronger.
The US economy keeps offering signs that underpin expectations the Federal Reserve will raise interest rates this year, with the majority of analysts betting on a September hike.
"Overall the data is certainly better in the second quarter," Dan Greenhaus, chief global strategist in New York at BTIG, told Bloomberg. "It keeps the Fed on track to raise rates this fall."
A Commerce Department report showed consumer spending rose 0.9 per cent last month, the largest advance since August 2009, extending a 0.1 per cent gain in April.
Separately, weekly jobless claims increased 3,000 to a seasonally adjusted 271,000 for the week ended June 20, the 16th straight week below 300,000.
"The labour market is tight, wages and incomes are rising solidly, so we should expect consumers to help lead the economy forward," Joel Naroff, chief economist at Naroff Economic Advisors in Holland, Pennsylvania, told Reuters