Ted Cruz’s campaign on Thursday released an ad aimed at front-runner Donald Trump in Nevada, drawing a plain contrast between the Texas senator and the billionaire on a potent topic in the Mountain West: federal land use.

“Eighty-five percent of Nevada is owned and regulated by the federal government, and Donald Trump wants to keep big government in charge,” Cruz says in the 30-second spot, titled “Nevada Land,” that will air in Nevada ahead of Tuesday’s Republican caucuses in the state. “That’s ridiculous.” 

Cruz says the land belongs to the people of Nevada, not Washington bureaucrats. “If you trust me with your vote, I will fight day and night to return full control of Nevada’s lands to its rightful owners, its citizens,” he says. “Count on it.”

In an interview last month with Field & Stream magazine, Trump said he didn’t support the federal government turning over lands in the West to the states. “I don’t like the idea because I want to keep the lands great, and you don’t know what the state is going to do,” Trump said. “I mean, are they going to sell if they get into a little bit of trouble? And I don’t think it’s something that should be sold.”