Sunak: China the 'greatest threat' to UK economy, responsible for major cyber attack
• China is 'greatest threat to UK's economic security' - Sunak
• Sunak said China is 'greatest state-based threat' to UK economic security
• Deputy PM to tell Parliament China responsible for 2021 cyber attack on Electoral Commission
• Commission said attack contained details of around 40 million people
• UK to accuse China of major hack as Beijing warns against 'smears'