Poland's foreign minister Jacek Czaputowicz resigned Thursday, the second top member of the right-wing government to quit this week.
The decision comes as Warsaw is involved in European diplomacy on the political crisis in neighbouring Belarus.
On Wednesday, Czaputowicz received prominent Belarusian opposition activists Valery and Veronika Tsepkalo.
His office gave no precise reason for the move, but said "the minister has in the past said that the post-election period was the right time for a change" in the post of foreign minister.
He hopes "that his successor will maintain the current line and support the strengthening of Poland's position on the international stage", his office told the PAP news agency.
President Andrzej Duda was returned to power in a run-off vote last month, backed by the populist right-wing Law and Justice (PiS) party.
The departure of Czaputowicz, who has been in the post since 2018, follows that of health minister Lukasz Szumowski on Tuesday.
Szumowski cited personal reasons for the decision. But Polish media have accused his ministry of failing to supervise the procurement of items such as face masks during the pandemic.