Leading Russian ecological campaigner Alexei Yablokov, the founder of Greenpeace Russia and one of the pioneers of the post-Soviet environmental movement, has died at 83, the Russian Academy of Sciences said Wednesday.

Yablokov, who studied marine zoology in the Soviet era, spearheaded major campaigns in the perestroika era that formed a new generation of activists and acted as advisor both to the government and various NGOs.

A respected scientist, Yablokov wrote seminal books, including scholarly titles and children's literature, and launched the country's first green party.

Despite old age and declining health, he continued to support environmental campaigns even as activism in Russia became increasingly politically risky and new legislation crippled many NGOs during Vladimir Putin's latest term as president.

He died on Tuesday in Moscow after a long illness.

Born in Moscow, Yablokov studied whales and dolphins before branching out into environmental policy, but "always remained true to science," Russian Academy of Sciences said in a statement.

He became a lawmaker in the Soviet Union's first popularly elected parliament and chaired its environment committee in 1989-91 before serving as president Boris Yeltsin's environment advisor.

In 1989, he founded the Soviet Union branch of Greenpeace, which three years later became Greenpeace Russia.

In 2005 he launched a short-lived green party called Union of Russian Greens, which later merged with the opposition Yabloko party, of which he became one of the leaders.

Yablokov "left a deep impression in all the fields he worked in: marine biology, nature protection and politics," said Maria Vorontsova, the head of the Russian branch of the International Fund for Animal Welfare.

For Russia's environmentalists, Yablokov was like "a true saint," said Dmitry Lisitsyn, an activist on the Far Eastern island of Sakhalin. "He was a truly extraordinary person" who served as an example, he said.

"He was one of the founders and the inspiration for Russia's modern environmentalist movement."