Contributors are having second thoughts about writing checks to the 9/11 memorial and museum because of the continued inter-governmental bickering over the site, Mayor Bloomberg said today.

“It’s getting harder to raise money,” Bloomberg declared on his weekly WOR radio show. “When we talk to them and try to solicit gifts (they say), ‘Well, you know, with the Port Authority (and) museum.”

Bloomberg and the Port Authority are about to reach the one-year mark of their stalemate over who will control the yet-to-be-opened museum, for which the mayor has privately raised more than half of the $700 million cost.

The mayor indicated he couldn’t believe things have gotten as far as they have.

“If you told me there would be disagreement on something as pure and simple as this,” he said. “It’s a shame we can’t get together.”

On the plus side, four million visitors have trooped to the site and “it does not seem to be slowing,” the mayor said.