AUGUSTA, Maine (AP) – The Penobscot Nation is formally vacating a seat it has held in Maine’s Legislature for more than 150 years amid tensions between the state and American Indian tribe.

The tribe will instead select an ambassador to work with state and federal governments. The Portland Press Herald reports that the change is a symbolic, historic shift rooted in chilled relations between state officials and Maine’s federal recognized tribes.

Tribal leaders say state officials have failed to respect the tribes’ sovereignty. They also feel the state has violated the tribes’ right to self-government on issues such as fishing and domestic violence prosecutions.

Tribal representatives can sit on committees and introduce bills, but they cannot vote. The Penobscots and Passamaquoddies withdrew their representatives to the Legislature in protest in May 2015.