RALEIGH — North Carolina Democratic Gov. Roy Cooper says the Republican-controlled legislature is again trampling on his authority, this time through the state budget that lawmakers passed this summer.

In a legal filing Tuesday, Cooper asserted that the legislators used budget provisions to unconstitutionally usurp his role in recommending and administering state budget provisions. The filing expanded a lawsuit that Cooper originally filed in Wake County court in May complaining that new GOP-passed laws prevent him from performing his gubernatorial duties.

Cooper vetoed portions of the two-year budget that legislators approved in June. The House and Senate overrode that veto.

One provision that Cooper disputes requires the governor to include money in his future budget proposals for taxpayer-funded scholarships for private school tuition. The 2016 budget law directed that state funding for the Opportunity Scholarships increase by $10 million annually through 2028, reaching $145 million.

Cooper, who opposes what critics call education vouchers, argues in the lawsuit that it’s unconstitutional for legislators to tell him as “director of the budget” what to put in his spending recommendations.

“By dictating what the governor must include in his proposed budget, the General Assembly is exercising core executive power in violation of separation of powers,” Cooper attorney Jim Phillips wrote in the lawsuit.

Cooper also challenged other provisions that direct how to spend federal block grants and North Carolina’s $87 million initial share of a nationwide emissions settlement with Volkswagen. These funds should be administered by the executive branch, in accordance with either federal law or a federal court, the lawsuit says.

The original lawsuit also challenged GOP-approved laws that Cooper argued eroded his powers to appoint state Court of Appeals judges and members of board and commissions.

Republican legislative leaders, who are among the defendants in the lawsuit, have defended the challenged laws while criticizing Cooper for using the courts to wage a political fight.

Cooper “asked our court system to anoint him as both the governor and the legislature at the same time,” Senate leader Phil Berger, a Rockingham County Republican, said Tuesday in a release. “We expect the judiciary will see through his thinly-veiled power grab, follow the (state) Constitution and dismiss this frivolous lawsuit.”

With mixed results so far, Cooper also has sued over recent laws combining the state’s elections and ethics panels, subjecting his Cabinet to Senate confirmation and giving civil service job protections to political appointees of GOP predecessor Gov. Pat McCrory. Some of the measures were passed last December, two weeks before Cooper was sworn in to office.