Tens of thousands of Russian troops remain in and around Ukraine, NATO Secretary-General Jens Stoltenberg said on Thursday, Eurasia Diary reports citing Yeni Safak. 

"We have seen some reduction in the number of Russian troops, but tens of thousands remain, and we are also seeing that Russia has kept a lot of weapons ... and equipment," said Stoltenberg in a doorstep statement ahead of a meeting of the EU defense ministers in Brussels.

The NATO chief said Russia was also imposing restrictions in the Black Sea, including on access to the Sea of Azov through the Kerch Strait, adding that NATO should remain vigilant and closely monitor the developments.

"Overall, there is a significant Russian presence, and there are many more Russian troops now, in and around Ukraine, than before the recent increase in tensions," he added.

Stoltenberg also welcomed the inclusion of the US, Canada, and Norway in the EU's Permanent Structured Cooperation (PESCO) and said: "Non-EU allies play an essential role in protecting and defending Europe."

As part of the NATO exercise Steadfast Defender 2021, NATO is deploying thousands of troops in Romania, he also said, adding that this "demonstrates how we mobilize and exercise NATO troops, and also how we're able to deploy them across Europe."

"And as part of this exercise, there are soldiers from the United Kingdom, from the United States, from Turkey, so it demonstrates also the importance of moving NATO troops quickly through Europe and that's also a reason why military mobility is so important."