Polish Prime Minister Donald Tusk arrived Friday in Armenia following visits to Georgia and Azerbaijan, where energy ties topped the agenda in the resource-rich region.
Warsaw has for several years lobbied for access to Azeri crude oil through proposed extensions to the Odessa-Brody pipeline to northern Poland.
Odessa-Brody travels currently in a reverse direction, though plans include extensions and route transfers through the Caucasus.
Razi Nurallayev, a member of the opposition Popular Front Party, told Radio Free Europe/Radio Liberty that Tusk's activity in the region ignored sensitive political and human rights issues.
"I think Poland is sacrificing fundamental freedoms for economic interests," he said.
Amnesty International in a January report said Azerbaijan had a "troubling record of human rights abuses," including tight media restrictions and pressure on minority groups.
Tusk said of his visit that it was time to put new weight behind plans for Odessa-Brody.