WASHINGTON — Sen. Marco Rubio, R-Fla., will serve as the acting chairman of the Senate Intelligence Committee, replacing Sen. Richard Burr, R-N.C., who stepped aside last week after FBI agents seized his cellphone while investigating stock sales he made before the coronavirus pandemic crashed global markets.

"The senior senator for Florida is a talented and experienced Senate leader with expertise in foreign affairs and national security matters," Senate Majority Leader Mitch McConnell, R-Ky., said in a statement. "Senator Rubio was the natural choice for this temporary assignment on the basis of accumulated committee service. His proven leadership on pertinent issues only made the decision easier."

McConnell said Rubio accepted his invitation to lead the panel.

Among the first tasks for Rubio will be a committee vote Tuesday on President Donald Trump's nominee to be director of national intelligence, Rep. John Ratcliffe, R-Texas. The vote is expected to be along party lines, which would favor his confirmation in the Republican-led Senate.

Rubio, a member of the Intelligence and Foreign Relations committees, is a national security hawk who had been widely expected to take over the committee once Burr retires. The senator from Florida unsuccessfully sought the Republican presidential nomination in 2016.

Under normal circumstances, Rubio would have to give up his gavel at the Small Business Committee, which is usually a sleepy panel with little profile but has been transformed into the leading overseer of the $650 billion Paycheck Protection Program created in the wake of the pandemic.

Since his appointment to run the Intelligence Committee is technically only temporary, Rubio may seek a waiver from GOP rules and ask to retain his chairmanship of the Small Business Committee. Normally, the odds of such a waiver would be slim, but the seniority ladder would put Sen. Rand Paul, R-Ky., a libertarian, in line to replace Rubio at a critical point in the committee's history. Some Republicans may be reluctant to put Paul in that position. Any attempt at a waiver would be dealt with Tuesday at the weekly GOP policy lunch.

Burr stepped down from the panel amid the investigation of his stock deals. He has denied wrongdoing and asked the Senate Ethics Committee to investigate.

FBI agents, acting with approval from the "highest levels" of the Justice Department, served a search warrant for Burr's cellphone and took the device from his Washington-area home, according to people familiar with the matter, who, like others, spoke on the condition of anonymity because the investigation is ongoing. Investigators also obtained a search warrant to examine data in the senator's cloud storage for his iPhone, people familiar with the case said.

The Washington Post's Paul Kane contributed to this report.