Starbucks CEO Howard Schultz has agreed to testify in a U.S. Senate hearing about the coffee chain’s alleged union busting after pressure from Sen. Bernie Sanders.

The Senate’s Health, Education, Labor and Pensions, or HELP, Committee was scheduled to vote Wednesday morning on whether to subpoena Schultz, who previously declined a request to appear. Sanders, a democratic socialist who represents Vermont, serves as chair of the committee.

Schultz is now scheduled to appear at a March 29 hearing.

“I look forward to hearing from Mr. Schultz as to when he intends to end his illegal anti-union activities and begin signing fair first contracts with the unions,” Sanders said in a statement Tuesday.

In February, Starbucks’ general counsel wrote in a letter viewed by CNBC that since Schultz is stepping down as interim CEO in March, it would make more sense for another senior leader with ongoing responsibilities to testify. Newcomer Laxman Narasimhan is slated to take over as chief executive in April.

“Through the agreement reached today, our testimony will seek to foster a better understanding of our partner-first culture and priorities, including our industry leading benefit offerings and our long-standing commitment to support the shared success of all partners,” Starbucks said in a statement.

As of Tuesday, 290 Starbucks locations have voted to unionize, according to National Labor Relations Board data. More than a year after Starbucks Workers United won its first election, none of the cafes have agreed to a contract with Starbucks yet.

Since Schultz returned to the helm of the company in April last year, Starbucks has taken a more aggressive approach in its opposition to the union push. The union has filed more than 500 charges of unfair labor practices with the NLRB, including allegations of retaliatory firings and store closures. The company also raised wages and improved benefits for non-union workers.

Starbucks has lodged more than 100 of its own complaints against the union, alleging intimidation and harassment.