US President Joe Biden announced on Friday that 30 countries will join the United States and put "tens of millions" of barrels of oil on the market to stop escalating prices due to the war in Ukraine.

"Nations are coming together to stop [Russian President Vladimir] Putin from using their energy resources as a weapon," the head of state told reporters at the White House.

Quoted by Lusa and the newspaper Económico, Biden announced that today 30 nations reached an agreement to increase the supply of oil on the market, meet demand, and try to lower prices.

The US head of state did not reveal which nations reached that agreement, but on Thursday the White House announced that the US was talking to the 30 countries that are part of the International Energy Agency (IEA).

IEA members held an extraordinary meeting today to discuss possible actions to bring stability to the international oil market.

This meeting comes just one day after Biden ordered the release of a record amount of his country's oil reserves - one million barrels a day over the next six months - to try to stem rising prices.

Biden's plan will serve to add a total of 180 million barrels of oil to the global market (one million per day for 180 days or six months), but the impact may be relative because the US contribution represents only 1% of global demand.

In addition, Russia has stopped putting about three million barrels per day on the market.

Biden already revealed on Tuesday that he was coordinating with his allies around the world and that he expected other nations to come forward with contributions of between 30 and 50 million barrels of oil.

The IEA already agreed on March 1, a week after the Russian invasion of Ukraine, to release 60 million barrels of oil from its members' strategic reserves.

At the time, the United States put 30 million barrels of oil on the market, only half of what the IEA agreed to.

Thursday's announcement by Biden has already had an effect on the markets and, in fact, the price of 'West Texas Intermediate', which is used as a reference in setting US oil prices, opened this Friday down 1.3%, to $98.95 (89.59 euros) a barrel.

The IEA is made up of Australia, Austria, Belgium, Canada, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Japan, Luxembourg, Mexico, New Zealand, South Korea, Slovakia, Spain, the USA, Norway, the Netherlands, Poland, Portugal, the Czech Republic, Sweden, Switzerland, Turkey, and the United Kingdom.