"To pay in rubles -- if this is not foreseen in the contract -- is a breach of our sanctions. We have about 97% of all contracts that explicitly stipulate payments in euros or dollars," she said.

An oil price cap is one of a number of proposals being discussed as EU ambassadors prepare for talks in coming days about more sanctions on Moscow — the sixth such package since Vladimir Putin ordered the invasion of Ukraine two months ago.

"The document says the rule is about HS codes, so it is applicable to all origins," a South Korea-based source said. "This should help Russian coal demand more than other origins because it is already at a discount to other origins."

Brent rose 67 cents, or 0.6%, to $105.66 a barrel , WTI gained 44 cents, or 0.4%, to $102.14 a barrel.

"As of the end of the business day on April 26, Gazprom Export had not received payments for gas supplies in April from Bulgargaz (Bulgaria) and PGNiG (Poland) in rubles," Gazprom said in a statement.

Brent were down 56 cents, or 0.5%, at $101.76 a barrel, WTI were down 56 cents, or 0.5%, at $101.76 a barrel.

The price of OPEC basket of thirteen crudes stood at $101.93 a barrel

Traders are keeping a close watch on whether a resolution can be found on the Kremlin’s demand to be paid in rubles for its gas. European Union lawyers have said the new mechanism violates existing sanctions, and Russian President Vladimir Putin has warned that flows could be cut if the terms aren’t met.

Brent was down $4.91, or 4.6%, at $101.74 a barrel, WTI fell $5.00, or 4.9%, to $97.07.

The price of OPEC basket of thirteen crudes stood at $107.66 a barrel on Friday,

"EU companies can ask their Russian counterparts to fulfil their contractual obligations in the same manner as before the adoption of the decree, ie. by depositing the due amount in euros or dollars," the EC said in the document.

U.S. Rig Count is up 2 from last week to 695 , Canada Rig Count is down 2 from last week to 101.

Brent was down 76 cents, or 0.7%, at $107.57 a barrel, WTI declined 32 cents, or 0.3%, to $103.47.

The price of OPEC basket of thirteen crudes stood at $108.81 a barrel on Thursday, compared with $107.97 the previous day, according to OPEC Secretariat calculations

Combined, Russia's seaborne crude and key oil products exports stood at 6.79 million b/d so far in April, down 640,000 b/d from 7.43 million b/d in February,