WARSAW - Poland may have to build a barrier on its border with the Russian exclave of Kaliningrad to stop a wave of African and Asian migrants who could start trying to cross in the coming weeks, a top Polish official said on Tuesday.

Poland accuses Russia and its ally Belarus of using migrants as part of a "hybrid warfare" campaign to destabilise Europe, and with tension running high due to the war in Ukraine, Poland fears a repeat of a crisis that saw thousands of African and Middle-Eastern migrants try to cross the Belarus border in 2021.

At that time, Minsk denied engineering the situation by flying in people seeking to enter the European Union, instead blaming Warsaw and Brussels for a humanitarian crisis that led to the deaths of several migrants in forests along the border.

Krzysztof Sobolewski, general secretary of the ruling Law and Justice party, told public broadcaster Polskie Radio 1 that Poland was considering building a barrier, similar to the one it has constructed on the Belarus border, on the frontier with Russia's Kaliningrad.

"We will have to strengthen our forces on this section of the border and also consider ... building similar border fortifications to those we now have on the Polish-Belarusian section," he said.

Russian media has reported that Kaliningrad has opened its skies to flights from the Middle East and Asia in a bid to attract more airlines and tourists.

"After what we had to deal with, and are still dealing with on the Polish-Belarus border, and considering the opening of the skies above the Kaliningrad region for aeroplanes from Turkey, Syria and Belarus, it could be in the coming weeks," Sobolewski later told Reuters, referring to increasing arrivals of migrants.

Kremlin spokesman Dmitry Peskov told reporters in a briefing that Russia would not interfere with any such decision.

"History proves the stupidity of decisions to build walls every time, because over the years or decades, all walls fall," he said.

Sobolewski said there were signs of larger groups of migrants appearing at the Belarus border.

Poland has built a 5.5 metre (18 feet) tall steel barrier, equipped with motion sensors and cameras, stretching for about 187 km (116 miles) on the Belarus border.

Poland had previously said that the border guard had received funds to build an "electronic barrier" of sensors and cameras on the Kaliningrad border.

(Reporting by Alan Charlish and Pawel Florkiewicz; Editing by Robert Birsel)