Since Prince George's County Council members voted to allow billboards in certain commercial areas of the county last week, County Executive Winfield M. Kelly Jr. has been getting a lot of heat from a local newspaper and a large number of citizens.

"Veto that bill," was the word coming from what one of Kelly's aides described as "the weather vanes of the community."

But under Maryland law, when the council considers zoning measures such as the billboard law, Kelly has no such authority.

So he called in Gerard T. McDonough, his closet ally on the council, and the two came up with a plan.

When the Prince George's council members met again yesterday for their weekly zoning session McDonough announced that he had changed his mind. He was now prepared, he said, to vote against the bill, nd he wanted his colleagues to reconsider it.

"I had no problems with the merits of the bill," McDonough said yesterday about the measure that would require council permission to put up each one. "I don't think it makes it easy to put a billboard up at all.

"But we have an election a month off and there are misconceptions in the community about the bill. For one reason or another the intent of the bill has not been properly communicated."

A blatant political move? McDonough was asked. "It's an astute political move," he answered.

Council member William B. Amonett moved that the bill be sent back to committee for reconsideration, effectively delaying it until at least next year. A voice vote was taken. The result was unanimous. Kelly had his veto.