JEFFERSON CITY, Mo. (AP) - Some Missouri union leaders have agreed to work around the clock to speed up construction of a Boeing aircraft plant if Missouri is awarded the project.

Gov. Jay Nixon announced an agreement Tuesday involving several construction union councils in the St. Louis area.

The unions said they would make workers available to Boeing for 24 hours a day in three, eight-hour shifts. They said that would eliminate the need for overtime while speeding up construction by at least a year.

Missouri is one of several states competing to build the Boeing 777X commercial airplane after union members in Washington state rejected a proposed contract that sought concessions.

Nixon has called a special legislative session to consider incentives. He says the labor agreement should make Missouri's offer more attractive.

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