Employees of Crown Resorts in Melbourne downed tools on Tuesday, October 15, and threatened the first strike in 16 years to press for wage increases and better conditions.

The workers are planning to refuse to serve alcohol during the key spring racing season, according to local television.

The United Workers Union said it will ask workers to endorse 24-hour strikes and may be in a position to take action from November 1, the day before Derby Day.

The workers are demanding a five per cent annual pay increase as well as better conditions, such as full-time contracts.