Polish Defense Minister Mariusz Blaszczak said construction of a temporary barrier along the Polish-Russian border was due to begin on Wednesday.
The 2.5-meter (8-foot) high and 3-meter deep barrier will be built along the Russian exclave of Kaliningrad, said Blaszczak.
Work on the barrier is due to be completed by the end of 2023.
Why is Poland building a fence along the Kaliningrad border?
With tensions over Russia's invasion of Ukraine, Polish authorities have suspected that Moscow plans to facilitate illegal border crossings by Asian and African migrants into the EU through Kaliningrad.
Blaszczak said he ordered the measure to strengthen Poland's security "by sealing this border" after a recent decision by Russia's aviation authority to launch flights from the Middle East and North Africa to Kaliningrad.
According to the Polish Border Guard, there were no illegal entries from Kaliningrad into Poland in October.
"The Polish-Russian border is stable and calm. There has been no illegal crossing of the border," Anna Michalska, a Border Guard spokesperson, said.
"We are not only there in times of peace. We are prepared for various crisis situations and after what happened on the Polish-Belarusian border we are even more prepared for everything, for all of the darkest scenarios," she added.
What happened on the Poland-Belarus border last year?
Poland's defense minister said the Kaliningrad barrier would be similar to what Warsaw built along the Polish-Belarusian border after a major standoff with Minsk last year.
Thousands of African and Middle Eastern migrants were trapped on Belarusian borders as they sought to cross into EU territories.
The EU and its member Poland accused Minsk, a close Russia ally, of using the migrants as part of a "hybrid warfare" on the bloc in a bid to destabilize it.
Rights groups accused Polish border guards of forcibly pushing migrants and asylum-seekers back into Belarus. According to Doctors without Borders (MSF), at least 21 migrants died.
The barrier along the Belarusian border was completed in June.
fb/nm (AP, Reuters)