Sen. Chuck Grassley returned to the Capitol on Monday after he finished a quarantine period following a positive coronavirus test.
In a statement, the 87-year-old Iowa Republican said he "did not experience symptoms" after his positive test on Nov. 17. Grassley, the oldest GOP senator, is the president pro tempore of the Senate and third in the line of presidential succession.
The senator encouraged Americans to wear masks and practice social distancing as he called for Congress to approve another aid package.
"Congress must do its part and pass long overdue relief legislation to help families, businesses and communities get through this crisis," he said. "I hope my colleagues reach the same conclusion and a bipartisan bill can pass very soon."
At least seven U.S. senators have tested positive for Covid-19 as a surge in infections grips the country. Grassley is the second-oldest member of the chamber and faced an increased risk of a severe illness.
When he went into quarantine, Grassley missed a vote in the Senate for the first time since 1993.