Moscow, Russia: Russian President Vladimir Putin on Saturday congratulated his ‘dear friend’ Cuban revolutionary leader Fidel Castro on his 90th birthday.

‘You enjoy deep respect in Russia as an outstanding statesman who devoted his entire life to serving the people of Cuba,’ Putin wrote in a telegram posted on the Kremlin’s website.

‘It is hard to overestimate your personal contribution to the development of friendship and cooperation between our countries,’ the Russian leader wrote.

‘I wish you good health, longevity, vitality and prosperity.’

Both loved as a hero and hated as a dictator, Castro is one of the giant figures of modern history who defied the United States to turn his island nation into a firm ally of the Soviet Union.

Ties between Moscow and Havana suffered after the collapse of the USSR as the massive flow of financial aid from Moscow dried up, delivering a major economic blow to the country.

Ex-KGB agent Putin has sought to bolster ties with Havana as he increasingly squares off against Washington and last met a frail Castro in 2014 during a visit to Cuba.