SYDNEY, Australia — Prime Minister Scott Morrison of Australia has proposed imposing stricter limits on immigration to control overcrowding in the country’s major cities, a plan that experts called a politically motivated gambit that could legitimize resentment against immigrants.

Population growth has played a major role in the country’s economic success, but people in Australia’s biggest cities are concerned about an influx of immigrants, Mr. Morrison said in a speech Monday night.

“They are saying: enough, enough, enough,” he told influential figures in Sydney’s business, media and urban planning sectors. “The roads are clogged, the buses and trains are full. The schools are taking no more enrollments. I hear what you are saying. I hear you loud and clear.”

On Monday, Peter Dutton, the home affairs minister, said he supported the proposal as one way to confront worsening congestion in Sydney and Melbourne, Australia’s most populous cities. “We want people out of cars and spending more time with their families, more time doing the things they want,” he said at a news conference.