Greenpeace activists detained in Russia for a protest against Arctic oil drilling will be formally charged with piracy on Wednesday, the Interfax news agency said.

If found guilty, the 30 detained activists could face a maximum punishment of 15 years in jail.

"They will be charged... (with) piracy committed by an organised group," Interfax quoted a law enforcement source as saying on Tuesday.

The source said the 30 detained activists will be charged in the northern city of Murmansk.

A Greenpeace representative said that the group's legal team had been advised that only two activists would be charged on Wednesday -- dual US-Swedish national Dima Litvinov, a spokesman for the organisation, and Finn Sini Saarela.

"We have had no formal information of what charges will be laid against the two activists in question. Any charge of piracy against peaceful activists would be absurd and have no merit in international nor Russian law," Greenpeace spokesman Aaron Gray-Block said.

President Vladimir Putin last week raised hopes that the activists would face lesser charges when he said that they "are not pirates", but had nonethless broken international law by protesting close to a Russian oil rig.

The crew of Greenpeace's Arctic Sunrise icebreaker was detained last month over the protest and detained for two months.

They are now in pre-trial detention centres in the cities of Murmansk and Apatity, nearly 2,000 kilometres north of Moscow and above the Arctic circle.

Greenpeace crew in 'shock' in Russian jails: activist
Moscow (AFP) Oct 01, 2013 - Greenpeace crew members detained in Russian jails for two months over their open-sea protest against Arctic oil drilling are "close to shock" over their conditions, a rights activist said Tuesday.

The 30 detained are being held in pre-trial detention centres in the cities of Murmansk and Apatity, which are nearly 2,000 kilometres (1,250 miles) north of Moscow and above the Arctic Circle.

All but four of the activists are non-Russians from countries including Britain, the United States, Finland and Argentina.

Russia has jailed the activists from Greenpeace's Arctic Sunrise protest ship without charge pending an investigation into alleged piracy, after several scaled a state-owned oil rig on September 18.

The activists have complained of cold cells and a lack of suitable clothing and food, said Irina Paikacheva, the head of a state-connected regional prisoners' rights watchdog.

"Many of them are in a state close to shock," she told AFP after visiting the prisoners. "They had never expected that they would face such consequences for their peaceful protest in a democratic state."

The foreign detainees are struggling to make themselves understood since virtually none of the prison staff speaks English, she said. One of the activists has consulted a psychologist.

Several of the foreign nationals have been placed in cells with Russians even though this breaches Russian law, Paikacheva added.

A Polish activist is sharing a cell with four Russians, while one of the British activists has two Russian cellmates, both accused of robbery.

Several non-smoking activists also complain of being placed in cells with chain-smokers.

Greenpeace spokesman Aaron Gray-Block said in e-mailed comments that several of the detained activists "need prescription medication".

"A number of others are taking over the counter medications such as paracetamol for problems such as mild arthritis and back pain," he said.

A young Finnish female activist is a vegan and unable to eat prison food, Paikacheva said, adding that prison officials had denied her request for vitamins to be delivered to her.

Under Russian law, prisoners have to hand in their watches and wear shoes without laces. The Finnish activist lacks a thyroid gland and needs to take medicine regularly -- hard to do without a watch.