According to Polish government estimates, up to a million Ukrainian refugees could flee to Poland, if Russia invades Ukraine.
Sasin said that he had received assurances from the US that it would provide support to help with refugees, if Poland needs it in the event of conflict.
As part of wide-ranging talks the minister also described Polish-US economic cooperation as "strategic" following his meeting with the US Secretary of Energy, Jennifer Granholm in Washington.
On Monday, during his three-day visit to the US, Sasin took part in the signing of a contract between the Polish copper and silver company KGHM and the US SMR technology developer NuScale Power on the development of six small modular nuclear reactors (SMRs) in Poland.
He also met the head of the International Monetary Fund Kristalina Georgieva and the US Secretary of Energy Jennifer Granholm.
"The USA is a strategic partner for Poland," Sasin wrote on Twitter after the talks, thanking Secretary Granholm for the meeting.
"We mainly talked about specific business solutions in the field of large-scale nuclear energy and Poland's potential in the supply of American LNG to Europe," he said.
Monday was the first working day of Sasin's US visit. On Tuesday, he is due to visit the New York Stock Exchange and meet with its management. On Wednesday, the Polish official will visit KGHM's Robinson copper mine in Nevada, where he will meet with its employees. (PAP)