It has been suggested that this means Nigel Farage is still technically leader but he resigned some time ago. The Electoral Commission may still have him listed as leader because Diane James didn't formally accept her nomination but he isn't the leader of the party any more.
Who will take the reins while a new leadership election is held is a bit of a mystery. Paul Nuttall resigned as deputy leader at the party conference last month and no replacement has been appointed. Presumably that will fall to Paul Oakden as party chairman.
Here is Diane's statement in full:
It is with great regret that I announce that I will not be formalising my recent nomination to become the new Leader of the party with the Electoral Commission.
Having won the enthusiastic support of party members, I was nominated by them as the new Leader at the recent UKIP Bournemouth conference.
Since that time, I have been in discussion with party officers about the role. It has become clear that I do not have sufficient authority, nor the full support of all my MEP colleagues and party officers to implement changes I believe necessary and upon which I based my campaign.
For personal and professional reasons, therefore, I will not take the election process further.
I will continue to concentrate fully on my activities and responsibilities as an elected Ukip Member of the European Parliament for SE UK region.
This is my final media statement on this issue.