The National Endowment for Democracy, a nonprofit that has had bipartisan support over decades for its work promoting democracy abroad, is suing the U.S. government and cabinet officials for withholding $239 million in congressional appropriations.

       Members of the group’s board, which includes current and former Republican and Democratic lawmakers, said the organization filed the lawsuit on Wednesday afternoon as a last resort because it had been unable to get the State Department to restart the flow of money.

       The group is also asking a court to prevent the government from withholding any future funds appropriated by Congress.

       The group has had to put about 75 percent of its staff on unpaid leave, and about 1,800 grant projects have received no money since late January, after President Trump signed an executive order freezing all foreign aid.

       In the lawsuit, filed in Federal District Court for the District of Columbia, the group argues that its money from Congress is not foreign aid and does not fall under the purview of the State Department, which manages the transfer of funds, or any other executive branch agency. Withholding the funding, the board members say, is illegal.

       Peter Roskam, a former Republican congressman from Illinois who chairs the nonprofit, said the board voted on Tuesday to go to court.

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