NEW YORK — President-elect Donald Trump is announcing his choices for three key administration jobs Friday, naming Alabama Sen. Jeff Sessions for attorney general, Kansas Rep. Mike Pompeo to head the CIA and former military intelligence chief Michael Flynn as his national security adviser.

All three have been fierce critics of President Barack Obama’s handling of terrorism and national security, and their selection likely signals a sharp shift in U.S. policy. In tapping Sessions and Flynn, Trump is also rewarding a pair of loyalists who were among his most ardent supporters during the presidential campaign.

Trump planned to announce the picks Friday, according to a senior transition official. The official insisted on anonymity in order to disclose the decisions ahead of Trump’s announcement.

Trump is a foreign policy novice and his early moves on national security are being closely watched both in the U.S. and overseas. Sessions and Pompeo would both require Senate confirmation before assuming their designated roles; Flynn would not.

Even with Republicans in control of the Senate, Sessions could face obstacles. He withdrew from consideration for a federal judgeship in 1986 after being accused of making racist comments while serving as a U.S. attorney in Alabama.

Sessions, the first senator to endorse Trump, has been a leading proponent of tough immigration enforcement policies. He’s tangled with the past two Democratic-appointed attorneys general on whether terrorism suspects deserve the protections of American civilian courts and on the planned closure of the Guantanamo Bay detention facility. He’s also been protective of the attorney general’s right to refuse a legally unsound directive from the president.

Pompeo is a conservative Republican and a strong critic of Obama’s nuclear deal with Iran. A three-term congressman, he graduated from the United States Military Academy at West Point and from Harvard Law School.

Pompeo has said that Muslim leaders are “potentially complicit” in terrorist attacks if they do not denounce those made in the name of Islam. “They must cite the Quran as evidence that the murder of innocents is not permitted,” he said in a 2013 House floor speech.

Flynn was a critic of Obama’s military and foreign policy long before he began advising Trump on national security issues during the presidential campaign. As national security adviser, Flynn would work in the West Wing and have frequent access to the new president.

The 57-year-old has been outspoken in his warnings about the dangers of Islamist groups, saying the U.S. needs to “discredit” radical Islam. He’s called Islam a “political ideology” and said it “definitely hides behind being a religion.”

Flynn has also worried some national security experts with his warmth toward Russia. Like Trump, he’s called for the U.S. to work more closely with Moscow.

Last year, Flynn traveled to Moscow to join Russian President Vladimir Putin at a celebration for RT, a television channel funded by the Russian government. Flynn said he had been paid for taking part in the event and brushed aside concerns that he was aiding a Russian propaganda effort.