Gov. Andrew Cuomo in a letter this week to the Internal Revenue Service decried the potential for the agency to block the ability of states to create a workaround to the $10,000 cap on state and local tax deductions.

Cuomo and state lawmakers agreed this year to the mechanism that is meant to circumvent the cap, essentially allow local taxpayers to contribute to a government-created charitable organization in order to continue the deduction.

Other states impacted by the cap have created similar mechanisms and the IRS is determining whether they can continue on.

In the letter, Cuomo argued the IRS’s proposed regulation blocking the charitable deductions “has no basis in law.”

“In taking aim at our charitable contribution programs, the federal government is once again revealing its true hostility toward New York,” Cuomo wrote in the letter to the IRS. “These proposed regulations continue the politically motivated economic assault on New York that started with President Trump and his allies in Congress. The IRS should not be used as a political weapon.”

The IRS is taking public comments this month on the regulation and Cuomo has vowed a legal challenge to oppose the cap, which was part of the December 2017 tax law changes.

“Make no mistake: New York will fight back. This proposal must be withdrawn,” Cuomo said. “And if it is not, we will pursue all options to resist this attack on our State, including litigation if necessary.”