Secretary of State Marco Rubio will testify before the U.S. Senate on Tuesday morning, arguing for the State Department’s annual budget request in a session also sure to cover pressing national security issues such as President Trump’s negotiations with Iran and an intensifying U.S. pressure campaign against Cuba’s government.

Mr. Rubio, who also serves as Mr. Trump’s national security adviser, will appear at 10 a.m. Eastern time before the Senate Committee on Foreign Relations, which is reviewing the State Department’s budget request for the 2027 fiscal year.

Such sessions typically turn into wide-ranging discussions of a department’s priorities, and Mr. Rubio will appear at a busy moment in U.S. foreign policy. Mr. Trump has been pursuing an interim deal with Iran that would extend an existing cease-fire, open the Strait of Hormuz and begin detailed talks on Iran’s nuclear program, and his negotiation positions and tactics have been drawing criticism from both supporters and critics of the war with Iran.

Mr. Rubio has played a key role in the Iran deliberations, as well as in U.S. policy toward Cuba, whose economy the Trump administration is choking in an effort to force Havana’s communist government into major reforms.

In past appearances before Congress, Mr. Rubio has proved an agile spokesman, firmly representing Mr. Trump’s overall views while often reinterpreting the president’s most incendiary remarks in more moderate terms.

Mr. Rubio will appear before the House Committee on Foreign Affairs for another budget hearing on Wednesday morning.