The Montgomery County Council voted unanimously yesterday to put a proposal on the November ballot that would expand the council by two members and require five members to be elected from districts rather than at large, as they are now.

The council, seeking to regain its preeminent control over the county planning process, also voted to place two other controversial questions on the ballot. The questions would poll voters on whether two state laws, which will increase the power of future county executives in planning matters, should be repealed.

County Executive Charles W. Gilchrist has said he will sue the council if it places these two questions, which both would be amendments to the county charter, on the ballot because they contradict state law.

"Mr. Gilchrist remains adamant in his opposition to charter amendments with no meaning which will mislead the citizens and cost significant amounts of money with no purpose," said Paul McGuckian, county attorney.

The referendum on changing council election methods was recommended in June by the Charter Review Commission, a bipartisan commission appointed in 1983 by the council. The council now has seven members; all run at large, but five must live in separate residential districts.

The proposal to expand the council to nine members would keep the existing five districts. However, under the proposal, candidates for those five seats would be elected only by the voters in those districts in an effort to make them more representative of local areas. Candidates for the four other seats would run at large.

Council member Esther P. Gelman opposed the change, saying it would create "a much larger, much less powerful council," but she said she supported placing the question on the ballot because she was "willing to give it a shot" with the voters.

A change in council election methods has been debated for more than a decade. A 1984 referendum to amend the county charter and elect five council members by district and two at large was defeated after heavy lobbying by the county Democratic Party and the League of Women Voters.

The referendum questions on the power of the executive in planning matters would not be binding, but Planning Board Chairman Norman L. Christeller, the driving force behind the proposals, said he hopes a vote on them would send a signal to legislators to repeal the state laws.

The laws, adopted this year by the General Assembly after heavy lobbying by Gilchrist, granted new authority to the county executive to veto master land use plans, the basic blueprints for development in Montgomery, and to appoint two of the five Planning Board members. Previously, only the council had those powers.

But council member Rose Crenca, who along with council member Scott Fosler opposed putting the two planning questions on the ballot, said the measures would confuse voters and have no meaning because they are not binding.

"You don't use the ballot to sample citizen opinion," Crenca said. "We're playing games with the voters. We're confusing them."

In other action, the council voted to oppose a Rockville site for construction of a major Motor Vehicle Administration facility. Last week it sent a letter to state officials opposing the site.

MVA is expected to announce today that it is abandoning its consideration of the Rockville location, and will explore other options, sources said.