Volume was generally light, with very little economic data this week and traders eyeing Friday's early close for Memorial Day weekend.

On Monday, China accused the United States of harboring "extravagant expectations" for a trade deal, underlining the gulf between the two sides as US action against China's technology giant Huawei began hitting the global tech sector.

"Right now with all the trade fears going on, everybody is rushing to safety here," said Stan Shipley, fixed income strategist at Evercore ISI in New York.

"If you look at economic data, it looks fine in the US and elsewhere too, but people are very worried about the tariff battle here."

In mid-morning trading, US 10-year note yields slipped to 2.389pc, down from 2.393pc late on Friday.

Yields on US 30-year bonds were also lower at 2.814pc , down from 2.824pc on Friday.

On the short end of the curve, however, US 2-year yields were slightly up at 2.206pc, compared with Friday's 2.202pc.

Analysts said a US economy is not nearing recession, but the risk increases if the trade war with China escalates further.

"We've long maintained that the economic expansion's greatest vulnerability comes in the form of a spike in uncertainty leading businesses to scale back spending plans," said BMO Capital Markets in a research note

"This eventually risks flowing through to the labor market as hiring slows, thereby undermining consumer confidence and spending. Hence, a recession is born."

BMO said it's too soon for this scenario to happen, although recent soft US retail sales figures contradicted Federal Reserve Chairman Jerome Powell's stance that the first quarter's weak consumption was temporary.

In a week with few economic reports on the schedule, the highlight is the release on Wednesday of the minutes of the Fed's last monetary policy meeting. Analysts, however, do not expect surprises from the minutes.