A Petrobras oil platform floats in the Atlantic Ocean near Guanabara Bay in Rio de Janeiro.

Oil prices tumbled nearly 6% on Thursday, extending steep losses in the previous sessions, as the market braced for a prolonged U.S.-China trade war and digested disappointing manufacturing data. Some analysts also pointed to signs that Middle East tensions are moderating.

Brent crude futures sank $3.35, or 4.7%, to $67.64 per barrel around 2:20 p.m. ET (1820 GMT). The international benchmark for oil prices hit a nearly two-month low earlier in the session and is on pace for its worst week since December.

U.S. West Texas Intermediate crude futures settled $3.51 lower at $57.91 per barrel, tumbling 5.7% to the lowest closing price since March 12. WTI is on track to end the week 7.7% lower and post the worst weekly performance in five months.

"The $60 level is a critical support point," said John Kilduff, founding partner at energy hedge fund Again Capital.

"After $60, really it's right down around $58 or so. Theoretically, if this thing really becomes a washout, $52 is the downside objective," he said, cautioning that the move would not happen overnight.

Crude futures fell with the stock market as the ongoing U.S.-China trade dispute entered a new phase. A wave of companies is suspending business with Huawei after the U.S. blacklisted the Chinese telecom giant.

Washington and Beijing are set to increase tariffs on hundreds of billions of dollars of one another's goods, raising concerns about a global economic slowdown and weaker demand for oil.

U.S. manufacturing activity grew at its slowest pace since September 2009 this month, according to IHS Markit.

Meanwhile, data released overnight showed Japanese manufacturing activity fell into contraction in May. Manufacturing activity for the European Union and Germany also came in below expectations.

Economic forecasting firm Oxford Economics on Thursday warned that weak crude demand appears to be spreading from developed nations to developing economies.

"One particular surprise is that China was weak in March, with diesel demand acting as a significant drag," Oxford said in a research note. "We are currently forecasting 4% oil demand growth for this year, but this assumes a significant acceleration in the remainder of 2019."