EARTH CITY • Gov. Eric Greitens on Tuesday signed into law a measure that will prevent Missouri cities from requiring union-level wages in public construction projects, a move he said will bring the taxpayers more efficiency, but that critics say is the latest in a pattern of union busting from the new Republican governor.

“We’ve sent a very clear message and that is that Missouri is open for business,” Greitens said at a signing ceremony in an Earth City retooling plant, where he was flanked by Wisconsin Gov. Scott Walker, the former Republican presidential candidate who made his national name challenging unions.

“Gov. Greitens is doing what he said he was going to do,” Walker told reporters. He said the measure Greitens signed ensures that “everybody can compete” for public sector construction jobs “instead of that money going into the hands of union bosses.”

The new law effectively bans “project labor agreements,” or PLAs, in which local governments require companies to pay union wages to their workers when they carry out tax-funded building projects such as schools and roads. Under the measure, Missouri cities and counties that require PLAs could be penalized with the loss of state funding or tax credits.