The Dutch government has announced a sharp cut in highway speed limits and changes in farming practices, as it struggles to address a pollution problem that threatens to become an economic and political crisis.

The Netherlands’ top administrative court ruled in May that the country was in violation of European Union pollution laws, a finding that threatened to block thousands of construction and farming projects, which could bring much of the economy to a standstill.

Prime Minister Mark Rutte said Wednesday that his government’s plan to address the problem would include a reduction in the daytime speed limit to 100 kilometers per hour from 130 kph, or to 62 mph from 81 mph. The limit will not change at night because fewer drivers are on the road.

The modification will go into effect as soon as possible, Rutte said, and he gave no indication of when — or even whether — it might expire.

“It’s a rotten measure; nobody likes it,” he said at a news conference. “But something of larger importance is at play here. It’s necessary to prevent that the Netherlands shuts down and also, especially, to prevent that jobs will be lost unnecessarily.”

The changes are a serious concession for the prime minister and his center-right People’s Party for Freedom and Democracy, which has pursued higher speed limits, pro-business policies and major construction projects.

The pollutants in question are nitrogen compounds — major components of air, water and soil contamination — that result from tailpipe emissions, but the primary source of them is livestock waste.

In addition to the speed reductions, Rutte announced changes in the feed given to farm animals and an increase of 60 million euros, about $66 million, in subsidies for pig farmers, to reduce nitrogen output.

After some lawmakers recently raised the idea of imposing cutbacks on raising pigs and chickens, farmers drove their tractors into The Hague in protest, severely disrupting traffic for days.

It was not clear whether the changes would move the Netherlands into compliance with the pollution rules.

Rutte said he would seek the passage of an emergency law to allow vital infrastructure projects, such as strengthening the dikes that shield much of the low-lying country from flooding.

He described the pollution issue as the most difficult he had faced in nine years as prime minister — even tougher than “the refugee crisis of 2015-2016 in its complexity and how to handle this,” he said.