The EU Commission said it is not intimidated by Belarus threats to stop gas transit from Russia to the EU.
Belarus President Alexander Lukashenko has threatened to cut off gas to Europe in retaliation for any new sanctions imposed over the migrant crisis on his country's border with EU member Poland.
"If they impose additional sanctions on us... we must respond," Lukashenko told government officials in comments released by the presidency on Thursday.
"We are warming Europe, and they are threatening us," he said, pointing out that Russia's Yamal-Europe pipeline transits through Belarus to Poland.
"And what if we halt natural gas supplies?"
Lukashenko also claimed that migrants on the border had been receiving weapons and explosives from conflict-riven eastern Ukraine for the past two days.
"Why are weapons coming here? They want to stage a provocation," Lukashenko said, adding that the Belarusian military should be vigilant.
The EU Commission has said it is not intimidated by Belarus threats to stop gas transit from Russia to the EU.
"We have seen threats, what we are saying is that we are not going to be intimidated by any potential action by the Belarus regime using gas as a tool", a Commission spokesperson said.
The statement came during a regular news meeting where the Commission declared that the EU will seek to blacklist airlines that transport Belarus migrants.
Migrants have been trying to cross the Belarus-Poland border for months but the crisis reached a new level when hundreds made a concerted effort this week and were pushed back by Polish borders guards.
Western governments accuse Lukashenko's government of luring them to his country and sending them to cross into Poland in retaliation for previous sanctions over Minsk's crackdown on the opposition.
On Wednesday, EU chief Ursula von der Leyen said the EU would hit Belarus with fresh sanctions next week over the crisis.
Poland has accused Minsk of "state terrorism" for using intimidation to force migrants to breach the border.
Belarus has in turn accused Poland of violating international norms by blocking the migrants and beating them back with violence.
Lukashenko said there were a lot of children and pregnant women among the refugees, adding they should receive the necessary help.
"There are a lot of women who are eight or nine months pregnant," he said. "When they are due of course we'll take them to the hospital and look after them further."