U.S. stocks retreated as Greece's debt negotiations seemed to have experienced difficulties one more time. Parties still disagree on reform requirements. At the same time some investors were selling off before the end of the second quarter.

The Dow Jones industrial average fell by 178.00 points, or 0.98%, to 17,966.07. The Standard & Poor's 500 fell by 15.62 points, or 0.74%, to 2,108.58. The Nasdaq Composite dropped 37.68 points, or 0.73%, to close at 5,122.41.

Dow component Boeing dropped 1.0% after naming Dennis Muilenburg as its next CEO, effective July 1. The company is also reportedly slowing production of its 747-8 jet due to weak commercial aircraft demand.

In Asia Hong Kong Hang Seng fell by 0.37%, or 101.95 points, to 27,303.02. China Shanghai Composite Index advanced by 0.23%, or 10.59 points, to 4,700.74. Meanwhile the Nikkei declined by 0.18%, or 36.62 points, to 20,831.41.

Asian stocks were also affected by Greece's situation. However yesterday the Nikkei managed to hit an 18-year high reaching 20,868.03.