Ukrainian President Volodymyr Zelenskyy asked nationals to take up arms after Russia launched an invasion against his country on Thursday, as he said the Russian military suffered heavy losses.

Speaking to reporters, Zelenskyy said Ukraine broke off diplomatic relations with Russia, as he urged Russians to come out and protest against the war. It marked the first rupture in ties since Russia and Ukraine became independent countries after the Soviet Union's collapse in 1991.

Ukrainian officials say the country’s military is fighting back and asked for Western defense assistance.

Ukraine has four consulates - in St Petersburg, Rostov-on-Don, Yekaterinburg and Novosibirsk - in addition to the embassy in Moscow.

Ukraine's permanent representative was already recalled to Kiev for consultations after Russia recognized the eastern Ukrainian separatist regions of Donetsk and Luhansk as independent states earlier this week.

Foreign Minister Dmytro Kuleba had recently advised Zelensky to break off diplomatic ties.