Oil prices were up nearly 1 percent on Monday, taking Brent above $50 a barrel and U.S. crude to three-month highs after comments by Iran’s leader exhorting the need for other oil producers to join OPEC in supporting the market.

Iran’s President Hassan Rouhani told his Venezuelan counterpart Nicolás Maduro in a telephone conversation that it was essential for oil producing countries to take a decision to raise the price of oil and stabilize the market, Tehran state news agency IRNA reported.

Rouhani’s remarks added to the bullish fervor in the market since last week after the Organization of the Petroleum Exporting Countries announced its first planned output cut in eight years.

Brent was up 36 cents, or 0.8 percent, at $50.55 a barrel by 12:49 p.m. EDT (1649 GMT). The session peak was $50.90, its highest since Aug. 19.

U.S. West Texas Intermediate (WTI) crude climbed 26 cents, or 0.5 percent, to $48.50. It earlier hit $48.87, its highest since July 5.

Crude futures were volatile, moving up again by noon in New York toward session highs after drifting most of the morning due to a weaker Wall Street and a stronger dollar. [.N] [USD/]

“It’s kind of a light volume day and we’re moving from headline to headline, but still Iran telling Venezuela that all countries are going to have to join this production cut is gaining traction because there are many who want to believe this deal will get done,” said Phil Flynn, analyst at the Price Futures Group brokerage in Chicago.

“There’s already a soft commitment from Russia that it will be part of the OPEC plan and if more non-OPEC members get on board, prices can only go higher.”

Oil prices rose about 7 percent in September, ending up a second straight month, after OPEC unveiled plans to reduce output to between 32.5 million and 33.0 million barrels per day.

How much oil each country will produce is to be decided at the next formal OPEC meeting in November, when an invitation to join cuts could also be extended to non-OPEC countries such as Russia.

OPEC’s oil output likely reached 33.6 million bpd in September from a revised 33.5 million bpd in August, its highest in recent history, a Reuters survey found on Friday.

OPEC member Iran, the No. 4 crude exporter, will sign on Tuesday a new petroleum contract that would be cornerstone to raising its crude output to the pre-sanction levels of 4 million bpd.

“Naysayers will undoubtedly fade the headline (of the output cut) and deem the agreement typical OPEC noise, yet at a minimum it means that OPEC has bought themselves a price floor for at least the next two months heading into the November meeting,” analysts at RBC Capital Markets said in a note. REUTERS