MOSCOW, June 17-- Russia might introduce sanctions against Ukrainian leaders in response to a "political war" it believed declared by Kiev, a senior Russian lawmaker said Tuesday.

"A system of sanctions against Ukraine should be considered, including those on Ukrainian leadership personally," said Alexei Pushkov, head of the International Committee of Russian parliament's lower house, or State Duma. "Kiev has waged a political war on us."

Pushkov urged the Duma to stop considering Kiev as Russia's partner until Ukraine demonstrates its readiness for partnership.

On Monday, Russian Prime Minister Dmitry Medvedev accused the Ukrainian leadership of "losing adequacy," citing Ukrainian Prime Minister Arseny Yatsenyuk's refusal to settle a gas price dispute and the "paranoid behavior" of its acting Foreign Minister Andrei Deshchytsa, who has hurled insulting remarks on Russian President Vladimir Putin.

Russian energy giant Gazprom cut off gas supplies to Ukraine Monday in a row over unpaid bills, while Ukraine sought to recover around 6 billion U.S. dollars from Gazprom, which Kiev said were overpaid due to the "unfair" gas contract since 2010.

The decision was seen as a sign for the escalating tensions between the two countries.