SACRAMENTO -- The clock has finally run out on the threat by California Attorney General Jerry Brown and Gov. Arnold Schwarzenegger to sue the federal EPA over state emission restrictions.

Brown announced today he and Schwarzenegger had formally filed suit over a delay by the EPA in granting California permission to lower permitted emissions of greenhouse gases (GHG) from motor vehicles. The two gave the EPA notice in April they would sue if the EPA's "waiver" wasn't granted within six months, LNL reported.

California filed suit today in the U.S. District Court for the District of Columbia today aimed at forcing the EPA to take action on the state's request. The suit alleges that the time passed since the state first requested its waiver constitutes an "unreasonable delay."

"We have waited two years and the Supreme Court has ruled in our favor," Brown told the media today in announcing the suit's filing. "What is the EPA waiting for?"

California passed the controversial "Pavley bill," which mandates reductions in tailpipe GHG emissions of 30 percent by 2016, in 2002. Sixteen other states have either enacted or will enact similar tailpipe-emission laws since then and fourteen are expected to join the suit Thursday.