Texas Republican Gov. Greg Abbott ordered an investigation into a state-regulated hospital near the Texas-Mexico border after accusing it of advertising maternity packages overseas to attract foreign nationals seeking U.S. citizenship for their children.

In a letter to Texas Health and Human Services Commission Executive Commissioner Stephanie Muth, Abbott on Tuesday said Mission Regional Medical Center in Mission advertised "BIRTH PACKAGES IN SOUTH TEXAS" in foreign countries "in an apparent effort to profit from securing United States citizenship for their children," reports The Hill. 

Abbott directed the HHSC to determine whether the hospital violated state law or contractual obligations.

"Birth tourism is an illegal practice that exploits the extraordinary hospitality that the United States and Texas offer to millions of foreign travelers each year," Abbott said in a statement.

"Thousands of foreign travelers come to the United States under false pretenses to give birth and secure citizenship for their children. HHSC must investigate the hospital, a facility it regulates, for any violations of state law and contractual obligations."

Mission Regional Medical Center denied participating in any unlawful activity and said it has removed the promotional materials in question.

"The hospital does not support or facilitate any unlawful activity and is committed to complying with all applicable federal and state laws and regulations," a hospital spokesperson said in a statement.

"The marketing materials regarding maternity services are no longer in use due to any unintended misunderstanding," the spokesperson said. "We intend to work cooperatively and transparently with local and state officials. Our focus remains on delivering safe, high-quality care to every patient who seeks our services."

The public nonprofit hospital is regulated by the HHSC and is located in Mission, Texas, just north of the U.S.-Mexico border.

A spokesperson for the commission told The Hill on Wednesday that the agency is working "to immediately implement" Abbott's directive and has referred the matter to the Texas Health and Human Services Office of Inspector General.

Abbott also said he intends to work with the Texas Legislature "to strengthen state law and eliminate birth tourism in Texas."

"American citizenship is not for sale, and Texas will not permit our health care system to be used as a magnet for birth tourism," he wrote.

The investigation comes as Republicans have renewed their focus on birth tourism following last week's Supreme Court ruling against the Trump administration's effort to limit birthright citizenship.

White House Deputy Chief of Staff Stephen Miller said during a Fox News interview that the administration could consider restricting the entry of pregnant foreign nationals into the United States.

"You have to now think very carefully about who you let into your country, even on a temporary basis, because ... of the possibility, as you said, for birth tourism," Miller said.

Birth tourism, in which foreign nationals travel to another country to give birth, represents a small fraction of U.S. births.

The Migration Policy Institute reported earlier this year that as many as 26,000 children born annually in the United States could be linked to the practice, less than 1% of the nation's more than 3.5 million births each year.

Immigration experts have noted that U.S. Customs and Border Protection already has the authority under existing law to deny entry to foreign nationals, including pregnant women, without requiring additional legal authority.