A London court has issued an arrest warrant against jewellery designer Nirav Modi, the main accused in the USD 2 billion PNB scam case, in response to an ED request for his extradition in a money laundering case, officials said on Monday. They said the investigative agency has been informed about the issuance of the warrant by the Westminster Magistrate Court against Modi and he is expected to be put under formal arrest by the local police soon.