Protesting Russian action against the Greenpeace vessel Arctic Sunrise, an activist of the organisation, staged a two-hour protest inside a tent hanging from the second floor of the Eiffel Tower, on Saturday.

Reports said the Greenpeace activist who climbed atop the Eiffel Tower, unveiled a banner which read "Free the Arctic 30" and "Militants in prison, climate in danger."

The protestor climbed up the Eiffel Tower, and began the protest at around 9 am local time. The campaign ended two hours later as firemen forced the activist to climb down. Following the protest, French authorities closed the monument to tourists during the morning hours.

"We are here to send a message to the French government to do everything to secure the release of the 28 militants and two journalists," Cyrille Cormier, a Greenpeace campaigner, is reported to have told a press agency.

"Prime Minister Jean-Marc Ayrault is due to visit Russia next week. We are asking him to put this case on the agenda," he added.

Russia had sparked an international outcry after it's detained the vessel belonging to Greenpeace and arrested the 30 member crew who were protesting against the offshore ice-resistant fixed platform 'Prirazlomnaya' in the Barents Sea.

Two Greenpeace activists had scaled a state-owned oil platform to protest against Russian energy exploration in the Arctic. The Russian coastguard then boarded the "Arctic Sunrise" on Sept 19 and brought it to the port of Murmansk Oblast.

Global pressure is building on Russia to release the arrested activist with Netherlands, having approached the United Nations-backed International Tribunal for the Law of the Sea, requesting provisional measures to be re-supplied and allowed to leave the place of detention along with the crew and exercise the freedom of navigation.

Meanwhile, Russian investigators have said that they found illegal drugs on board the Greenpeace Ice breaker Arctic Sunrise on Wednesday.