NATO member Poland said Tuesday it will acquire combat drones as part of a multi-billion-euro revamp of its armed forces amid heightened tensions with Russia over its role in the Ukraine crisis.

"We will use these drones to defend our territory," Deputy Defense Minister Czeslaw Mroczek told AFP.

Ukraine is rearming and deploying new units to the east of the country to counter any attempt by pro-Russian rebels to take over more territory, President Petro Poroshenko said Tuesday.

At a crisis meeting of security chiefs in the capital Kiev, Poroshenko said that he had not given up on a deal brokered in September to end the seven-month conflict, in which more than 4,000 people have died.

Elections organized and won by separatists in eastern Ukraine over the weekend were "unfortunate and counterproductive," U.N. chief Ban Ki-moon said Tuesday.

Ukraine is rethinking its truce with rebels holding parts of the east of the country because separatist elections "violated" the agreement, President Petro Poroshenko said Monday.

"These pseudo-elections are a gross violation of the September 5 Minsk protocol," he said in an address to the nation, vowing to "re-examine" Kiev's commitments to the truce deal.

Russia has opposed a U.N. Security Council move to criticize rebel elections held in eastern Ukraine, the Ukrainian ambassador said Monday.

A statement from the 15-member council was discussed on Friday and again at the weekend, but Russia fiercely opposed it.

Ukraine's government still has options after separatist elections showed its helplessness against a Russian-backed rebellion. The problem: they're all bad.

Analysts and officials paint a grim scenario facing Ukraine's pro-Western government as it ponders how to respond to the separatists' tightening grip on the industrial south-eastern Donbass region.

A Malaysia-bound Malindo Air flight diverted to Thailand and made an emergency landing on Monday after the cabin started to de-pressurize, the airline said, adding that none of the 129 people aboard was hurt.

The Malaysia-based carrier's flight OD206 from Delhi had been due to arrive in Kuala Lumpur early Monday but instead re-routed to Bangkok after the incident, which caused oxygen masks to deploy inside the plane.

Europe on Monday warned Russia to respect Ukraine's unity as Moscow piled pressure on Kiev by recognizing controversial rebel polls aimed at giving legitimacy to a bloody pro-Kremlin insurgency.

German Foreign Minister Frank-Walter Steinmeier said the elections went "against the letter and spirit" of an internationally brokered truce deal in September that was meant to halt the war in eastern Ukraine.

Russia endorsed a crushing victory for Ukraine's pro-Moscow rebel leadership after controversial polls on Sunday that the EU slammed as a "new obstacle" for peace in the country's strife-torn east.

The swift acceptance of the results by Russia looked certain to spark a diplomatic firestorm, with a fresh round of Western sanctions against the Kremlin now increasingly on the cards.

The elections may already have been slammed as a farce by the West but those queuing to cast their ballots in east Ukraine's rebel polls on Sunday insisted their voices should be heard. 

"I hope that our votes will change something. Perhaps we will finally be recognized as a real, independent country," Tatyana, 65, said as she waited at a polling station at school number 104 in insurgent stronghold Donetsk.