Democratic presidential candidate Martin O'Malley took his pro-immigration stance to a new level Friday by declaring citizenship "a human right."

O'Malley, who has long been an advocate for illegal immigrant rights, has made amnesty a centerpiece of his campaign since he declared two months ago. His comments come in response to Texas health officials asking a federal judge to dismiss a lawsuit by immigrant parents who were denied birth certificates for their U.S.-born children.

"Denying birth certificates to U.S. citizens is not only outrageous, it's unconstitutional," O'Malley said in a statement on Friday. "The 14th Amendment of the U.S. Constitution could not be clearer. It states that 'all persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the state wherein they reside.'"

He added, "The Texas Department of State Health services should cease this discriminatory and unconstitutional practice immediately. Citizenship is a human right."

Without a birth certificate it can be difficult to prove residence for educational, medical and travel purposes. The Texas department of health services refused to issue the birth certificates because the immigrant parents did not have proper identification.

"As a result of this situation, hundreds, and possibly thousands, of parents from Mexico and Central America have been recently denied birth certificates for their Texas-born children," according to the lawsuit filed in May.

The case comes amidst President Obama's push to protect million of immigrants living illegally in the U.S. from deportation. Immigration has been a hot-button issue on the campaign trail as Democrats call for amnesty and Donald Trump calls for closing the border.