HARRISBURG — Pennsylvania Attorney General Kathleen Kane on Thursday rejected a long-term contract sought by Gov. Tom Corbett that would let a British firm manage the $3.5 billion Pennsylvania Lottery, saying parts of it contravene the state constitution or are not authorized by state law.

Her politically fraught decision came after Corbett undertook a nine-month process to find and hire a private company to replace state employees atop one of the nation’s largest lotteries. Corbett, who had endured months of criticism about the policy and process from Democrats, settled on London-based Camelot Global Services, the United Kingdom’s official lottery operator.

Kane announced her decision in a short statement read at a news conference at her Harrisburg offices, but declined to take questions from reporters.

“It is important that my office perform its role in the system of checks and balances that our government desperately needs and that our citizens deserve,” she said.

In a memo she sent Thursday to Corbett’s Department of Revenue, which oversees the lottery, Kane’s office revealed that it had asked Corbett to withdraw the contract because of a pending lawsuit filed by Democratic lawmakers and the union that represents lottery employees. Corbett refused.

Kane’s office subsequently decided that state law does not allow the governor to privatize the operation or management of the lottery nor does it allow the expansion of gambling that the contract would permit.

For now, it seems the lottery will remain managed by state employees, while it is not clear what will happen next with the contract.

Corbett can challenge Kane’s decision in court, but would only say Thursday that he did not agree with the attorney general’s analysis and was reviewing his legal options. Camelot’s bid expires Saturday, and it would not say Thursday whether it will agree to extend it.

House Republican leaders said they expected that the Legislature will review Kane’s decision.