NEW YORK: US Treasury yields turned lower on Monday, as investors worried about Brexit turmoil spreading to other assets, after Britain's Prime Minister Theresa May abandoned a parliamentary vote on her deal to exit the European Union.

UK 10-year yields fell to 1.16 percent, the lowest since late May. US yields, after trading mostly higher, fell in sympathy.

US 30-year yields dropped to three-month lows, while those on benchmark 10-year notes slid to their lowest since late August.

May said she was delaying a planned vote on Tuesday on her Brexit deal as she expected it to be rejected.

She said she would ask the EU for more "reassurances" over the main bone of contention: a "backstop" to ensure no hard border on the island of Ireland, which her critics say means Britain could end up indefinitely subject to EU rules after it leaves.

"The rally in Treasuries is presumably Brexit related," said Lou Brien, market strategist, at DRW Trading.

"Part of the weakness in stocks which has affected Treasuries is technical in nature, and part of it is the incredible uncertainty in the UK, which has added to the already uncertain situation here in the US," he added.

The 5-year and 30-year yield curve flattened somewhat on Monday, after two sessions of steepening. The flatter yield curve reflects growing uncertainty about geopolitical risks, analysts said.

Aside from Brexit, investors worried about China.

The arrest of Chinese company Huawei Technologies' chief financial officer Meng Wanzhou in Canada has threatened to derail a US-China trade deal.

Meng's arrest has unsettled global markets as investors worry it could halt attempts to ease trade tensions between the United States and China.

On the economic front, analysts are looking to US inflation data this week, which could determine the pace of future rate hikes.

Since late October, 10-year yields have fallen more than 20 basis points amid a mixed set of economic data, the latest being a weaker-than-expected US non-farm payrolls report.

"It's US inflation week and I can't remember a time when inflation numbers are as widely anticipated as jobs numbers," said Stan Shipley, fixed income strategist, at Evercore ISI in New York.

He still expects the Federal Reserve to raise interest rates at next week's monetary policy meeting, but after that, it's anybody's guess.

Shipley added that the market has reduced its rate hike forecasts for next year, with just one or two priced in, from original expectations of three to four.

In midday trading, US 10-year note yields fell to 2.841 percent, from 2.85 percent late on Friday. Earlier, they fell to a near four-month low.

US 30-year bond yields fell to 3.119 percent, from 3.143 percent on Friday, after earlier dropping to 3.103 percent, a three-month trough.

On the short end, US two-year yields were down at 2.704 percent, compared with Friday's 2.711 percent.