"I do not know in detail what happened, but it is quite clear that they are not pirates," Vladimir Putin told an international Arctic forum Wednesday in the Siberian city of Salekhard.

It was his first comment since 30 members of Greenpeace and its icebreaking ship were seized by Russian authorities last Thursday when activists tried to board an oil platform operated by Russian state oil concern Gazprom in the Pechora Sea.

Law 'violated'

Putin said it was "completely obvious these people violated the norms of international law" by going "dangerously close" to the Prirazlomnaya oil rig.

The international executive director of Greenpeace, Kumi Naidoo, welcomed the Russian president's "recognition" that the activists were not pirates "and acted purely out of concern for the Arctic environment."

Greenpeace had earlier called the detention of their members as "completely incomprehensible."

However, Putin defended law enforcement's handling of the situation, saying they could not have known whether the activists were terrorists or environmentalists.

"Our border guards did not know who was storming the platform under the guise of Greenpeace," he said.

Russian authorities had said the "most active" members of the group could be charged with piracy, but Putin's comments seemed to indicate otherwise. If convicted of piracy, they could face 10-15 years in prison. Investigative Committee spokesman Vladimir Markin said Wednesday the piracy charge could be changed once the investigation is completed.

Russian authorities had originally accused the activists, who come from 19 different countries including Russia, of terrorism.

Climate change concerns

In last week's protest, two activists tried to scale the platform but eventually slipped into the freezing water and were recovered by the Russian coast guard. Agents from Russia's Federal Security Service (FSB) then seized the Arctic Sunrise. A Russian tug towed the ship and its detained crew into Mumarsk harbor on Tuesday.

Rising average temperatures in the Arctic attributed to climate change and opening up of sea lanes have prompted energy producers to seek access to oil and gas reserves.

Greenpeace argues that oil spills and lack of precautions pose severe dangers to icy regions that are home to polar bears, walruses and rare seabirds.

dr,ipj/mz (AP, dpa, AFP)