Yes, the police are legally able to record a conversation with you. In fact, in any of your dealings with the police you should, out of an abundance of caution, assume that the conversation is being recorded.
Many people think that the police can only record you if you agree to participate in a formal police record of interview at the police station. That is incorrect. Police can telephone you and record that conversation and use it as evidence against you. By way of example, there have been numerous cases where the complainant has telephoned an alleged offender and that conversation has been recorded by the Police with the complainant’s consent. Such telephone calls are often made from a Police station.