Israel and Hamas have agreed to a four-day truce, according to the Associated Press, during which hostages will be released in exchange for Palestinians imprisoned in Israel.

Qatar, which has been acting as a mediator in conversations between Israel and Hamas, announced the deal on Wednesday. It will go into effect on Friday morning. As reported by the AP, 50 hostages held by Hamas will be released in stages, in exchange for 150 Palestinian prisoners. Women and children will be released first on both sides, and humanitarian aid in Gaza will increase.

The temporary ceasefire marks the biggest breakthrough since Hamas’ Oct. 7 attack on Israel, which prompted a full-out war. According to the AP, Israel Prime Minister Benjamin Netanyahu said that after the four-day truce, the war would resume “until we achieve all our goals.” However, Israel said it would extend the pause in fighting an extra day for every 10 additional hostages released by Hamas.

U.S. President Joe Biden welcomed the deal in a statement, saying: “I appreciate the commitment that Prime Minister Netanyahu and his government have made in supporting an extended pause to ensure this deal can be fully carried out and to ensure the provision of additional humanitarian assistance to alleviate the suffering of innocent Palestinian families in Gaza. I look forward to speaking with each of these leaders and staying in close contact as we work to ensure this deal is carried through in its entirety. It is important that all aspects of this deal be fully implemented.”