Wikileaks founder Julian Assange has agreed to plead guilty in a deal with the US Justice Department and return to Australia, court documents filed on Monday state. The agreement would see Assange pleading guilty to one charge of conspiring to obtain and disclose classified US national defence documents, according to court documents published on Monday evening. The deal is still to be approved by a US federal judge. Assange is expected to attend a hearing on the island of Saipan on Wednesday before returning to Australia, the court documents state. Assange is accused of having stolen and publi…