The striker hasn't yet put pen to paper, contrary to morning reports, but he's agreed to extend his time at Old Trafford in principle. Wayne Rooney is expected to sign a new contract with Manchester United by the end of the week. Rooney, out of contract at the end of next season, has agreed in principle a new four-and-a-half year deal worth £300,000-a-week that will keep him at Old Trafford until 2018. Although United dismissed reports claiming Rooney had already penned the new deal , they hope confirmation of the contract can be formally announced within the coming days. United executive vice-chairman Ed Woodward is currently on holiday, but an outline agreement over a new deal is understood to have been reached between the club and Rooney's representatives. Rooney's decision to commit the final prime years of his career to United is a major coup for United, Woodward and boss David Moyes, given the striker was set on leaving Old Trafford last summer. The breakdown of his relationship with Sir Alex Ferguson, plus Chelsea's determination to sign him, saw Rooney consider his United future, but the Old Trafford hierarchy stood firm and refused to sanction his sale.