Ted Cruz, Donald Trump's closest rival in the Republican race for the White House, named his national security advisers on Thursday, including an activist deemed by the Southern Poverty Law Center as one of the nation's leading Islamophobes.

Announcing the team in a statement, Cruz said he would reverse what he described as the weakening of the United States in a dangerous world, singling out militant Islamist groups in the Middle East and North Africa as his focus.

Among those were Frank Gaffney, a former official in the Reagan administration, and at least two other members of a think tank Gaffney founded, the Center for Security Policy. The center's reports argue that hundreds of thousands of American Muslims support Islamist violence in the United States and that there is a conspiracy to erode the U.S. legal system by elevating sharia, the Islamic legal code. Republican frontrunner Donald Trump cited research by Gaffney's group in announcing his plan to bar Muslims from entering the U.S. last year.

The Southern Poverty Law Center, a civil rights organization that monitors U.S. extremist groups, has labeled the Center for Security Policy a "hate group" and Gaffney a "notorious Islamophobe."

Gaffney did not respond to a request for comment, but a spokesman pointed to online essays where Gaffney has rejected such criticism, saying his group is a defender of civil liberties against "Islamic supremacists."

"Do you mention any of the other 22 members of the advisory coalition?" Brian Phillips, a Cruz spokesman, said in an email, declining to respond to questions about the criticisms made against Gaffney and his think tank.

The Council on American-Islamic Relations (CAIR), a Muslim rights group, urged Cruz, a Christian, to reconsider having Gaffney and others who have made anti-Muslim remarks as his advisers, saying it suggested the candidate entertained "anti-Muslim bigotry".

Besides Gaffney and his think-tank colleagues, CAIR said Cruz should drop William Boykin, a retired U.S. Army lieutenant general who has said the government should be allowed to ignore the U.S. Constitution to pass laws limiting Muslims' right to freedom of speech and religion.

Some of Cruz's other advisers have been critical of anti-Islamic rhetoric, including Abrams and Mary Habeck, another former Bush adviser; both have said Islam should not be demonized. Another adviser is Katherine Gorka, president of the Council on Global Security, a group that produces research on Islamist violence, who said in an email that Cruz "understands the vital role that America's military strength plays across the globe but without wanting to engage the U.S. in expensive democracy-building adventures."