‘Singham’ star Ajay Devgn is on a month-long vacation in London with his actress wife Kajol and two kids. Devgn, 44, who was last seen in Sajid Khan’s ‘Himmatwala’, recently completed shooting for Prakash Jha’s political drama ‘Satyagraha’ along with Amitabh Bachchan. “Off today to london. The holiday is finally here. See you guys in a month or so!,” Devgn posted on Twitter.