Polish Foreign Minister Radoslaw Sikorski said that Poland must shoot down Russian missiles over Ukraine before they enter its airspace. Other states bordering Ukraine should do the same, he added.
According to Sikorski, despite NATO's opinion on this issue, Poland must take this step to ensure the safety of its citizens.
"When enemy missiles approach our airspace, this would be legitimate self-defense," the head of the Polish Foreign Ministry said.
NATO membership does not cancel each country's responsibility to protect their airspace.
"This is our constitutional duty," Sikorski said.
Poland signed a bilateral security agreement with Ukraine, in which both countries pledged to look into "the possibility of intercepting missiles and UAVs launched in the direction of Polish territory in Ukrainian airspace."
NATO Secretary General Jens Stoltenberg rejected the proposal because the alliance could thus "be dragged into war with Russia.
According to Western officials, Ukraine is pushing its allies to become more actively involved in the conflict, including by providing air cover over Western Ukraine.
NATO Deputy Secretary General Mircea Geoana said that the alliance discusses decisions that are potentially dangerous for allies. Poland has always consulted other members before making such decisions, the official said.
NATO certainly respects the sovereign right of each ally to ensure national security" and plans to continue helping Ukraine, but the alliance will do everything possible to avoid escalation of the conflict, Mircea Geoana said.