BRUSSELS -- The 28-member NATO will hold emergency talks on Ukraine on Tuesday,

Ukraine crisis

the bloc announced in a statement Monday.

The upcoming meeting of the North Atlantic Council, which includes the ambassadors of all 28 NATO Allies, is convened at a request by Poland under article 4 of NATO's founding Washington Treaty, the NATO statement said.

Under article 4 of the Treaty, any member country of the bloc can request consultations "whenever, in the opinion of any of them, their territorial integrity, political independence or security is threatened," the statement said.

The NATO said the developments in and around Ukraine are seen to "constitute a threat" to neighboring Allied countries and "having direct and serious implications for the security and stability of the Euro-Atlantic area."

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