Szymon Szynkowski vel Sęk made the statement at a media briefing in Prague on Friday, public broadcaster Polish Radio reported.
Poland's top diplomat met with reporters after holding talks with his Czech counterpart Jan Lipavský.
Szynkowski vel Sęk said there were "suggestions at the EU level" to process the proposed amendments to the bloc's treaties "without discussion" among member states.
He said "Poland is against such an approach," as it "lacks transparency."
He told reporters that the Czech Republic had a "similar position."
Earlier in the day, the Polish foreign minister met with Slovakia's top diplomat Juraj Blanár in Bratislava.
Szynkowski vel Sęk told reporters that Slovakia "firmly opposes" the proposed changes to EU treaties, and takes a "similar view" to Poland on "migration issues and the performance of EU institutions."
Poland's top diplomat said the proposed amendments to EU treaties would threaten "the strategic powers of the Polish state."
He added that "Poland supports European integration" as long as there is recognition for the powers of the member states.
Szynkowski vel Sęk told the media that "quite a few" countries were "sceptical about the proposed EU treaty changes," adding that he would visit more capitals to discuss next steps.
Earlier this week, he attended a meeting of NATO foreign ministers in Brussels and spoke to his Lithuanian counterpart Jovita Neliupšienė in Vilnius, and Latvia's top diplomat Krišjānis Kariņš in Riga, according to the Polish foreign ministry.
Last week, the European Parliament adopted a set of proposals to amend EU treaties, a move designed to "give citizens a stronger say and create a more effective EU."
The main proposed changes include abolishing the principle of unanimity in the European Council in 65 policy areas, to be replaced by qualified majority voting; the transfer of powers from member states to the EU, in areas such as foreign affairs, external security and defence; and making the euro the mandatory currency for EU countries, Polish Radio's IAR news agency reported.
(pm/gs)
Source: IAR, polskieradio24.pl