MADRID -- Russia and Spain signed an energy agreement Tuesday that will give Spanish companies greater access to Russian fields and could smooth the path for Russian firms to buy stakes in Spanish companies.

The framework deal, which was unveiled at a joint news conference between Spanish Prime Minister Jose Luis Rodriguez Zapatero and President Dmitry Medvedev, covers the development of oil and natural gas as well as its transport and sale.

Zapatero was keen to point out that the agreement also included renewable energy, where several Spanish companies hold major positions, including wind turbine maker Gamesa and Iberdrola, a wind energy producer.

"[This agreement] opens the door to collaboration between our country and one of the biggest energy players in the world," Zapatero told a news conference in Madrid. "The memorandum means greater security in Spain's energy supplies, and it guarantees better access for our companies to Russian energy reserves."

Zapatero said Spain would make building energy ties with Russia a top priority when it takes over the European Union presidency in 2010.

Gazprom CEO Alexei Miller told reporters in Madrid that his company was also in talks with Spanish oil major Repsol over the development of the Yamal gas field and the participation of Repsol in LNG-related projects.

"We will consider the possibility of Spanish companies taking part in Russian projects, including Yamal. Gazprom is in talks about such participation with companies including Repsol," Miller said.

Medvedev played down recent rumors that talks between Sacyr and Russia's LUKoil over the sale of the Spanish builder's 20 percent stake in Repsol had been shelved because of price differences, saying "no one has closed the door on those talks."

Zapatero added that the question of whether or not talks continued between LUKoil and Repsol "is going to depend on the companies."

Concrete business deals arising from Medvedev's official visit to Spain were limited to a gas supply agreement between Gazprom and Gas Natural to export Russian gas to Spain.

"Thanks to the swap operations, these supplies will start in the near future, initially in small volumes. We will develop the project involving the Shtokman field, which will be launched in 2014," Miller said.

Spain's lberdrola said on Tuesday that it has signed a deal with leading Russian electricity dealer Inter-RAO to study opportunities in the Russian Federation, the EU and Latin America.