(ANSA-AFP) - WARSAW, NOV 9 - Polish Prime Minister Mateusz Morawiecki said Tuesday that an unprecedented wave of migrants trying to illegally enter Poland from Belarus threatened the security of the entire European Union. "Sealing the Polish border is our national interest. But today the stability and security of the entire EU is at stake," Morawiecki said on Twitter. "This hybrid attack of (Belarusian President Alexander) Lukashenko's regime is aimed at all of us. We will not be intimidated and will defend peace in Europe with our partners from NATO and EU." Belarus denied the charges that it was coordinating the attempted crossings. The Belarusian defence ministry called the allegations "unfounded and unsubstantiated" and accused Poland of "deliberately" escalating tensions. On Monday Poland blocked a bid by hundreds of migrants -- mostly from the Middle East -- to breach the razor-wire border fence as thousands more massed in the area. The latest grim chapter of Europe's migrant crisis saw Washington and Brussels call on Minsk to stop what they describe as an orchestrated influx. NATO on Monday also hit out at Minsk, accusing the government there of using the migrants as political pawns, while the European Union called for fresh sanctions against Belarus. (ANSA-AFP).