Ukraine's leader of the far-right Pravy Sektor (Right Sector) paramilitary movement Dmytro Yarosh has announced his presidential bid in elections planned for 25 May.

The ultra-nationalist movement's chairman Andriy Tarasenko said that Right Sector will also become a political party.

"Dmytro Yarosh will run for president," he said. "We are preparing for a congress, at which the party will be renamed, and we will participate in the elections in Kyiv, the elections in all local councils, towns and villages."

"We remain the leaders of this revolution. We are mobilising, we are preparing to react to foreign aggression," Tarasenko added, claiming that the movement was ready for a full-scale war with Russia.

A leading figure in the 2014 Ukrainian revolution, Yarosh advocated a "national revolution" during the protests and dismissed ousted Viktor Yanukovich's administration as an "internal occupational regime".

Yarosh, who considers the far-right Svoboda "too liberal", wants to ban both the former ruling party (Party of Regions) and the Communist Party of Ukraine.

Tarasenko distanced the movement from the pro-EU government led by interim president Oleksandr Turchinov.

"There has been no reset of power. Only the names in the government offices have changed," he was quoted as saying.

"Our struggle is entering a peaceful phase, a political phase and that is why we are going into politics," he said.

Russia opened a criminal investigation against Yarosh for incitement to extremism and terrorism.

Right Sector was condemned by the US State Department for "inflaming conditions on the streets".

In an interview with Time magazine, Yarosh revealed that the ultra-nationalist movement had amassed a lethal arsenal of weapons.

The movement's ideology, which rejects any foreign influence over Ukraine, borders on fascism, according to reports.

"For all the years of Ukraine's independence, Russia has pursued a systematic, targeted policy of subjugation toward Ukraine," Yarosh told Time. "So of course we will prepare for a conflict with them."