The battle for Labor to hold on the Tasmanian seat of Lyons is heating up, with former state Labor leader Rebecca White announcing she is retiring from state politics to focus on the federal election.

White has been preselected as the Labor candidate after Brian Mitchell announced he would not contest the next election. White led Labor across three election campaigns in Tasmania, but Labor fell short each time.

AAP reports White said she needed to concentrate her energies on the federal contest:

The time has come for me to step aside and focus my energy on the upcoming federal election campaign, where I hope to continue my service to our community of Lyons in the Australian parliament,” she said in a statement.

“It is with great excitement that I now dedicate myself to the task of winning the support of my community to represent them in the federal parliament.”

Labor is battling to hold on to Lyons, but White is seen as their best chance to retain the seat.