Yields at lows ahead of euro zone summit, auction

Getty Images. U.S. Treasury prices dipped on Tuesday, as focus turned to U.S. data and the first of this week's Treasury auctions - a $24 billion 3-year note sale.

U.S. Treasury prices rallied on Tuesday, pushing the 10-year yield below 2.20 percent, as investors awaited the outcome of a euro zone summit that will attempt to find a solution to the ongoing debt crisis in Greece.

The summit begins at 12 p.m. ET in Brussels and Greek Prime Minister Alexis Tsipras is under pressure to negotiate a deal as the country is running out of cash and the European Central Bank has tightened funding.

Bond yields, which move in the opposite direction to prices, edged higher in anticipation of the new supply. The yield on 2-year notes (U.S.: US2Y) was down 4 basis points to 0.557 percent, while the benchmark 10-year yield (U.S.: US10Y) was 9 basis points lower at 2.197 percent-the lowest in more than a month.

On the domestic front, data showed that the U.S. trade deficit widened less than expected in May, suggesting economists might raise slightly their forecasts for economic growth in the quarter.

Separately, U.S. employers advertised slightly more job openings in May, a sign of an increasingly energized economy where companies are expecting continued growth. The Labor Department says the number of open jobs rose 0.5 percent to 5.36 million in May.

Read More Greece fallout keeps tensions high

Still, the number of new hires in May and the number of workers who left their job-a sign of strength since quits are generally associated with people finding better jobs-slipped slightly.

The Treasury auction of 3-year notes meanwhile kicks of the first of three government bond sales scheduled for this week.

U.S. oil futures were trading at $51 a barrel in on Tuesday, more than 1 percent lower on the day having tumbled to three-month lows the previous session on concerns that a crisis in Greece and a rout in China's stock market will undermine global oil demand.

"It is hard to see much of an impact on Treasury or Bund prices from the move in oil, with Greece not even making much of a dent," analysts at Societe Generale said in a note.

-Reuters and the Associated Press contributed to this report.



More From CNBC