Update: Secondary legislation was passed on June 9, confirming the extension of the deadline for registration.
Minister for Cabinet Office, Matt Hancock, said:
Following discussions with the Electoral Commission and strong cross-party support expressed in the House of Commons, we will introduce secondary legislation to extend the deadline for voter registration until midnight tomorrow.
Having taken the decision today, we think it is right to extend to 23.59 on Thursday 9 June, to allow people who have not yet registered, the time to get the message that registration is still open and get themselves registered.
You can register to vote here