After the tragedy, both nations continued work on their space programs. However, both sides felt uncertainty about future missions. As diplomatic talks with the Soviet Union continued, the idea of joint missions started to enter foreign policy conversations. During the SALT 1 talks in May 1972, both President Nixon and Soviet Premier Alexei Kosygin signed an agreement “Concerning Cooperation in the Exploration and Use of Outer Space for Peaceful Purposes”. This would lead to the development of the Apollo-Soyuz Test Project (ASTP).
Photo courtesy of NASA, information from The Nixon Foundation:
https://www.nixonfoundation.org/2015/03/the-nixon-space-doctrine/
The Apollo- Soyuz Test Project 