Stocks are edging lower in the U.S. and elsewhere as investors close their positions ahead of the New Year and consider the possibility of political turmoil in Greece.

The Dow Jones industrial average fell 51 points, or 0.3 percent, to 17,985 as of 11:45 a.m. Eastern time Tuesday.

The Standard & Poor's 500 index lost five points, or 0.3 percent, to 2,085 and the Nasdaq composite was down 16 points, or 0.3 percent, to 4,790.

European markets fell. Greece's main index was down slightly.

Benchmark U.S. crude oil edged down 12 cents to $53.47 a barrel in New York. Oil has fallen about 50 percent since June.

Bond prices rose. The yield on the 10-year Treasury note fell to 2.18 percent.