SACRAMENTO (CBS / AP) — Gov. Jerry Brown is telling California lawmakers that he will call a special legislative session on health care at the end of the year.

In a letter dated Thursday, the Democratic governor told legislative leaders that many of the provisions of the new federal health law cannot be implemented without further guidance from federal officials.

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Brown does not specify exactly what he wants lawmakers to consider. The governor’s spokesman, Gil Duran, did not immediately return messages Friday.

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California has been among the most aggressive states in adopting rules to implement President Barack Obama’s signature law, which was upheld this year by the Supreme Court.

Rhys Williams, spokesman for Senate President Pro Tem Darrell Steinberg, says lawmakers still need to take up three health care-related bills before the end of August.

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