European election observers say presidential hopefuls running against Prime Minister Vladimir Putin face "biased" reports by Kremlin-controlled media and constant government pressure.

Tiny Kox, who heads the Council of Europe mission to Russia, said Saturday that all four candidates complain that Putin's government is using its "administrative resources" to influence voters, while Russian television extensively covers Putin's activities.

The candidates are Communist Party chief Gennady Zyuganov, nationalist Vladimir Zhirinovsky, socialist Just Russia leader Sergei Mironov and billionaire tycoon Mikhail Prokhorov.

(AP)