Raul Castro, the first Cuban president to visit Russia since the Cold War, signed a partnership pact with Kremlin leader Dmitry Medvedev on Friday intended to revive the once flourishing alliance between the two countries.

Castro, wearing a dark suit and white shirt rather than the battle fatigues beloved of his brother Fidel, opened a meeting with Medvedev by recalling the long-standing ties between Moscow and Havana -- a constant irritant to the United States.

"We are old friends, we have known each other in good (times) and bad, the ones when you really get to know friends best," the 77-year-old Raul said. "This is an historic moment, an important moment in relations between Russia and Cuba."

Medvedev congratulated Cuba on the 50th anniversary of its communist revolution and sent his best wishes to Raul's 82-year-old brother Fidel, who led Cuba since 1959 but retired as president last February due to ill health.

"Your visit to our country opens a new page in the history of Russia-Cuba relations and will mean their elevation to the level of strategic partnership," the Russian president said.

The formal meeting, which lasted under an hour, was followed by the signing of agreements giving Russian food aid and a $20 million loan to Cuba to buy Russian construction, energy and agricultural equipment.

Financing was agreed for the delivery of Tupolev 204 civilian aircraft and Russia will donate at least 25,000 tonnes of grain to help resolve food problems on the island.

Russian power company Inter RAO signed an agreement to build a power station in Cuba, and Russian vehicle manufacturers Kamaz, Avtovaz, Zil and Gaz are interested in operations in Cuba, Deputy Russian Prime Minister Igor Sechin added.

No figures were disclosed.

Castro did not give a news conference and details of his agenda in Moscow over the weekend were not available, even to the Cuban press pool travelling with him. Castro was to meet Russian Prime Minister Vladimir Putin on Monday.

Defence cooperation was not mentioned.

Moscow closed its last military installation in Cuba, a radar base which Washington said was used to spy on the United States, in 2002 as a cost-cutting move.

There was been no sign of any fresh attempts to establish facilities on the island.

Asked afterwards by a reporter about possible military cooperation between Moscow and Havana, Sechin responded: "Why are you interested in that ?"

REBUILDING

Moscow was Cuba's main benefactor during the Cold War but their alliance wilted after the 1991 collapse of the Soviet Union. Fidel Castro last visited Moscow in 1986 for a Communist Party congress.

But over the last few months both countries have moved to rebuild links. Russian oil companies want to drill in the sea around Cuba and its military has talked about air defence cooperation with the Cubans.

"It is our duty on the Cuban side ... to take the appropriate steps for the constant, serene but unstoppable consolidation of our relations in all aspects," Castro said.

"The strategic association we have agreed...reflects perfectly what we have achieved and what we aspire to achieve."

Medvedev visited Cuba in November during a tour of Latin America.

As well as power generation and vehicle manufacturing, Friday's agreements between Russia and Cuba also covered cultural links, education, and medicine.

"Solid foundations have been laid for the development of Russian-Cuban relations in the economic area," Sechin told reporters.

One possibility was a joint venture between Russian national carrier Aeroflot and Cuba's Cubana de Aviacion, he added.

Trade between Russia and Cuba totalled $239 million during the first 11 months of 2008, a 26 percent rise compared to the same period in 2007, the Kremlin said. Russia mainly buys sugar cane from Cuba and sells machinery.