Sir Keir Starmer is braced for a clash with unions as a Czech billionaire’s proposed takeover of Royal Mail reignites calls for nationalisation. The Communication Workers Union (CWU), which represents postal workers, is due to speak to Labour Party officials on Friday to discuss a £3.1bn takeover bid for the 500-year-old postal service by Daniel Kretinsky. The swoop has highlighted tensions between union bosses and the Labour Party over the renationalisation of privately-owned assets. In an emergency motion tabled at its conference on Thursday, the CWU said its policy was to bring Royal Mail back into public ownership. However, it admitted that “the current political climate makes delivering this very difficult”. The Labour Party is understood to oppose nationalisation. A Labour source said bringing the postal service under public ownership was “not an option”, adding that the party was instead interested in ways of boosting investment in its creaking network. Shadow business secretary Jonathan Reynolds met Mr Kretinsky, dubbed the Czech sphinx, in Davos earlier this year and the party is said to have developed a working relationship with the tycoon. Labour’s apparent openness to the takeover comes despite concerns about a critical British asset falling into the hands of...