WASHINGTON (Reuters) - The chief executives of social media companies Meta, X, TikTok, Snap and Discord will testify on online child sexual exploitation at a Jan. 31 U.S. Senate hearing, the Senate Judiciary Committee said on Wednesday.

Senator Dick Durbin, the panel's Democratic chairman and the ranking Republican Lindsey Graham said Discord and X had initially balked at participating and refused to accept a subpoena. "Now that all five companies are cooperating, we look forward to hearing from their CEOs," they said in a statement.

It will be the first appearance by TikTok CEO Shou Zi Chew before U.S. lawmakers since March when the Chinese-owned short video app company faced harsh questions, including some suggesting the app was damaging children's mental health.

Proposed legislation has stalled in Congress that would give the Biden administration new powers to block Americans from using foreign communications technology such as TikTok, which is used by more than 150 million Americans.

Durbin and Graham said the hearing will allow committee members to press CEOs from some of the biggest social media companies on their failures to protect children online.

Mark Zuckerberg, CEO of Meta, which owns Facebook and Instagram, X CEO Linda Yaccarino, Snap CEO Evan Spiegel and Discord CEO Jason Citron will testify.

"Big Tech’s failure to police itself at the expense of our kids cannot go unanswered,” Durbin and Graham said.

The committee this year has approved a number of bills including one that would remove tech firms' immunity from civil and criminal liability under child sexual abuse material laws that was first proposed in 2020.

Another would establish a National Commission on Online Child Sexual Exploitation Prevention and another to modernize investigations and prosecutions of online child exploitation crimes.