Poland is building new fortifications and shelters in the border zone with Belarus and Russia, as reported on Monday in a Polish economic and legal newspaper. 

A ministry source told the Rzeczpospolita daily that the move was "part of the overall national defense plan," and the Ministry of Defense did not disclose any detailed information. 

In a briefing, the ministry said, "Work is underway on the further expansion of engineering fortification, including a shelter system and their improvement in the border zone." 

"The situation is extremely critical, and the sense of urgency is spreading among numerous countries," Defense Minister Wladyslaw Kosiniak-Kamysz told the Daily Super Express. He further stated that he is gearing up for a potential scenario in which Ukraine faces defeat in the war with Russia.

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"I assume every scenario and take the worst ones most seriously. This is the role of the minister of defense in the situation we find ourselves in today. These are not words thrown into the wind. I try to weigh them very carefully," he said.

He stressed that "large purchases are very important. But for me, the individual equipment of soldiers is equally important. Since taking power, we have concluded contracts for purchasing equipment worth PLN19 billion (over $4 billion) -- most of it in Polish arms plants."

Polish Air Navigation Services Agency activates navigation warning 

On February 4, the Polish Air Navigation Services Agency consulted with the Air Navigation Operational Command and issued a navigation warning for airspace users.

The warning was activated on February 5 and will continue until May 5. It encompasses the airspace spanning the entire eastern region of Poland, bordering Ukraine and Belarus, the northeastern area adjacent to Lithuania and Russia (the Kaliningrad exclave), as well as the central portion of the country, including the capital city of Warsaw.

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During this time last year, Anna Michalska, a spokesperson for the Polish Border Guard, announced plans for an electric fence along Poland's border with Russia.

At the time, the Polish military was building a barbed wire fence along the border with the Russian Kaliningrad region. An estimated $84 million contract was signed in late 2022 to construct an electric fence along the Polish-Russian border.

"Building an electric barrier at the border with the Kaliningrad region should start in March. The electric system near the Kaliningrad region will run along a 200-kilometer [124 miles] land border area," Michalska said.