TRAVERSE CITY, Mich.  — It sounds like an idea that would warm a conservative Republican’s heart: Kill funding of a regional environmental cleanup that has lasted seven years and cost the federal government more than $2 billion, with no end in sight. If states want to keep the program going, let them pick up the tab.

That is what President Donald Trump’s 2018 budget plan proposes for the Great Lakes Restoration Initiative, an ambitious push to fix problems that have long bedeviled the world’s largest surface freshwater system — from invasive species to algal blooms and toxic sludge fouling tributary rivers.

During the Obama administration, the program generally got about $300 million a year. Trump’s offer is zero. His spending plan released Thursday says it “returns the responsibility for funding local environmental efforts and programs to state and local entities, allowing EPA to focus on its highest national priorities.”

The response from Republicans in Great Lakes states: No, thanks.

“I think it makes sense for us to continue to make prudent investments in protecting and improving the Great Lakes,” Wisconsin Gov. Scott Walker told The Associated Press, adding that he would lobby the Trump administration and congressional leaders to put the money back.