Poland's President Andrzej Duda had a phone conversation on Wednesday with U.S. President Joe Biden, the Chancellery of the President of Poland informed. Among the topics discussed, the chancellery said, was the upcoming summit of the Bucharest Nine format, NATO summit in Madrid, as well as issues related with Ukraine. "Also discussed were ways to increase Poland's security, as well as Polish-American cooperation in the fields of security and economy," President Duda's office added.