Four industry groups representing major internet providers and cable companies filed suit on Wednesday seeking to block California’s new law to mandate net neutrality rules.  

The groups represent companies including AT&T Inc, Verizon Communications Inc, Comcast Corp and Charter Communications Inc. The lawsuit came after the U.S. Justice Department on Sunday filed its own lawsuit to block the new law.

The lawsuit filed by the American Cable Association, CTIA - The Wireless Association, NCTA - The Internet & Television Association and USTelecom – The Broadband Association, called California’s law a “classic example of unconstitutional state regulation” and urged the court to block it before it is set to take effect Jan. 1.

U.S. Attorney General Jeff Sessions said on Sunday in a statement that the “the California legislature has enacted an extreme and illegal state law attempting to frustrate federal policy.”