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Sixteen US states have filed a lawsuit challenging President Donald Trump's national emergency declaration. The attorneys general from Colorado, Connecticut, Delaware, Hawaii, Illinois, Maine, Maryland, Michigan, Minnesota, Nevada, New Jersey, New Mexico, New York, Oregon and Virginia joined California in the lawsuit.

Trump intends to take executive action to re-allocate more than US$6 billion from funds appropriated by Congress for other purposes – principally out of the US Defense budget – to pay for a border wall with Mexico.

The Trump administration already faces a litany of lawsuits over the national emergency declaration. Over the weekend, the Center for Biological Diversity, Border Network for Human Rights and the American Civil Liberties Union all announced lawsuits.