Sen. Marco Rubio (R-Fla.) will not mount a challenge for the Senate Foreign Relations Committee chairmanship after Sen. Bob Corker (R-Tenn.) retires at the end of 2018.

“If Jim Risch wants to be chairman I’ll support him,” he told reporters on Wednesday. Rubio’s comments, which were confirmed by his office, were first reported by Politico.

Corker, the current committee chairman, announced on Tuesday that he will retire at the end of his current term, creating an opening for the top spot on the influential panel.

{mosads}Risch, aside from Corker, is the most senior Republican on the committee, making him next in line to become the chairman.

Rubio, however, quickly garnered speculation as a potential challenger because he’s been outspoken on foreign policy, including, at times, challenging the Trump administration.

Risch hasn’t said whether he will seek the committee’s gavel going into 2019. He’s currently the chairman of the Senate Small Business and Entrepreneurship Committee.

Asked on Wednesday if he wanted to take over after Corker retirees, Risch remained tight lipped but noted the Senate Republican Conference has rules that would determine who should succeed Corker.

“Right now I’m a committee chairman of another committee. I’ve got 15 months left to serve there. I’m totally focused on that. When we’re done with this you all know exactly where this is going,” Risch told reporters.

The two GOP senators are considered friendly, with Risch endorsing Rubio’s 2016 presidential bid.

In addition to being the second- and third-ranking Republicans on the Foreign Relations Committee, they also hold the No. 2 and No. 3 GOP spots on the Intelligence Committee. Rubio is the second-ranking Republican on the Small Business and Entrepreneurship Committee under Risch.

This report was updated at 3:45 p.m.