When does The Undeclared War return?

The Undeclared War is a British near-future thriller television series. The series is written by Peter Kosminsky and follows two main characters, Saara Parvin in the UK and Vadim Trusov in Russia, during a cyber and misinformation attack upon the UK. The first series aired from 30 June 2022 on Channel 4. Channel 4 announced on 12 February 2025 that a second series consisting of six episodes would be produced.