HAMILTON - Signs are pointing to a lockout of 900 workers tonight at the U.S. Steel plant in Hamilton.

A notice posted on the website for Local 1005 of the United Steelworkers of Canada says the union has received a letter saying the company will lock out workers as of 7 p.m. Sunday.

The union says the company is demanding unionized workers put a Nov. 4 offer to a vote.

The offer, which U.S. Steel calls "final," was sent through the mediator appointed by the provincial Ministry of Labour.

Negotiations on a new contract began in May. The main sticking points have been the company's demand for concessions on pensions, the cost of living formula and benefits.

U.S. Steel bought the former Stelco in 2007. It says the changes are needed for the plant to be competitive.