■ The European Union says more than 150,000 Russian troops have amassed near Ukraine.

BRUSSELS — The European Union’s foreign policy chief has estimated that more than 150,000 Russian troops have already amassed for the biggest military buildup ever near Ukraine’s borders and that it will only take “a spark” to set off a confrontation.

Josep Borrell also said Monday that the condition of imprisoned Russian opposition leader Alexei Navalny was “critical” and that the 27-nation group would hold the Kremlin accountable for his health and safety.

Despite the developments, Borrell said after a virtual meeting of the EU foreign ministers that, “for the time being, there is no move in the field of more sanctions” to be imposed on Russia.

He also said there wasn’t a request for a synchronized EU diplomatic move of expulsions in the standoff between Czech Republic, an EU member state, and Russia following Prague’s accusation that Moscow was involved in a 2014 ammunition depot explosion.

More dangerous at this time, Borrell said, was the massing of Russian troops, including military field hospitals, and “all kinds of warfare.”

“It is the highest military deployment of the Russian army on the Ukrainian borders ever. It’s clear that it’s a matter of concern when you deploy a lot of troops,” Borrell said. “Well, a spark can jump here or there.”

“There’s more than 150,000 Russian troops massing on the Ukrainian borders and in Crimea. The risk of further escalation — it’s evident,” he told reporters after the meeting.

More than 14,000 people have died in seven years of fighting between Ukrainian forces and Russia-backed separatists in eastern Ukraine that erupted after Russia’s 2014 annexation of Ukraine’s Crimean Peninsula. The EU has opposed the annexation but has been unable to do anything about it.