Crude prices fell further on Tuesday morning as investors continued to pin their hopes on diplomatic talks aimed at ending the US-Iran war.
Brent dropped 1.31% to $91.36 a barrel, while the main US contract, West Texas Intermediate, retreated 1.59% to $85.47 a barrel.
Both main contracts have lost around 20% this month as traders bet on a resolution to the seven-month-old conflict, which has sent inflation soaring and forced central banks to hike interest rates.
US President Donald Trump said on Monday there was "positive momentum" toward ending the war after meeting Qatar's prime minister at the White House.
"I had an excellent conversation with Sheikh Mohammed bin Abdulrahman bin Jassim Al Thani," Trump said on Truth Social, adding that "much was discussed with respect to the Islamic Republic of Iran".
While expectations had grown ahead of last week's midterms that he would resume strikes on Iran this month, Trump has talked down such a move while leaving the door open to them.
In his post on Monday, Trump reiterated that the United States was "locked and loaded", but that he believed further strikes were "quite unlikely" given that key US allies in the Gulf "would prefer the status quo".
His comments echoed early statements to CNN over the weekend when he said it was "highly unlikely" fighting would resume.
