BRUSSELS -- European Union ambassadors have prolonged asset freezes and visa bans on 146 individuals and 37 entities that, according to the bloc, have threatened Ukraine's territorial integrity.

The decision to prolong the measures by six months was taken on September 7, ahead of a September 15 deadline.

The sanctions were first introduced in March 2014 in response to Russia’s illegal annexation of Crimea.

Their targets include companies in Crimea and various battalions formed by the Russia-backed separatists in eastern Ukraine, as well as Russian politicians like Deputy Prime Minister Dmitry Rogozin and Dmitry Kiselyov, a state media executive and presenter whom many regard as the Kremlin's chief propagandist.

The EU's economic sanctions that target Russia's energy, military, and financial sectors are up for renewal on January 31 but will be discussed by EU leaders when they meet for an EU summit in October in Brussels.

A decision on the measures is expected when the EU heads of state and governments meet again in December.