THE dispute between coal giant Xstrata and workers at the Bulga open-cut mine appears set to escalate with the company planning to lock out workers for 24 hours from 7am today.
About 250 workers returned from a 49-hour strike at 8pm yesterday but will be locked out this morning.
United Mineworker's Union vice-president Greg Sharp said the news came after union members agreed to rolling stoppages and a ban on using some equipment, but were prepared to work.
"Our members will make themselves available at the start of every shift," he said.
He said the lockout seemed a strange move by Xstrata after already losing 49 hours of production in the previous strike.
"But then they have done a few strange things recently," Mr Sharp said.
Xstrata said the union's plan for rolling stoppages over the next 24 hours made it impractical to continue production during that time.
"The [union's] decision to disrupt production is not in the interest of our employees or the future of the Bulga operation," eastern operations general manager Greg Pawley said.
Mr Sharp said the union would look to continue talks with management on January 27.