The Chairman of the ISC, the Rt. Hon. Sir Malcolm Rifkind has this morning issued the following statement:

None of the current controversy with which I am associated is relevant to my work as Chairman of the Intelligence and Security Committee of Parliament.

However, I have today informed my colleagues that while I will remain a member of the Committee, I will step down from the Chairmanship.

The Committee is due to be dissolved in little over a month with the prorogation of Parliament for the forthcoming General Election. The main substantive work which needs to be completed will be the publication of our Privacy and Security Report during March.

I do not want the work of the Committee and the publication of the Report to be, in any way, distracted or affected by controversy as to my personal position. I have concluded, therefore, that it is better that this important work should be presided over by a new Chairman.

Will it be enough to lance the boil?

UPDATE: Rifkind also stepping down as an MP at the election. Kensington is in play.

UPDATE II: Personal statement from Sir Malcolm Rifkind:

“I have received tremendous support from my Constituency Association and from many constituents in Kensington over the last two days. However, I have been pondering whether it is fair to my colleagues and friends in Kensington to remain the prospective Conservative candidate for the forthcoming General Election. I warmly welcome the Committee that has been established by the Party to examine the controversy with which I have been associated and to report by the end of March on its conclusions. It will be an excellent opportunity for an objective assessment of the allegations that have been made and I will be happy to cooperate closely with the Committee. However, it is unlikely that it will be able to finish its deliberations until well into March and there, obviously, can be no certainty as to its conclusions. I am conscious, therefore, that Kensington Conservatives are faced with serious uncertainty until the end of March as to whether I will be able to be their candidate. If I could not they would have little time to choose a new candidate. I am also aware that even if the Committee reach a favourable conclusion as to these allegations the controversy will remain during what is certain to be a heated General Election and, indeed, for many months thereafter until the Parliamentary Commissioner for Standards has completed the necessary enquiry. I had intended to seek one further term as MP for Kensington, before retiring from the House of Commons. I have concluded that to end the uncertainty it would be preferable, instead, to step down at the end of this Parliament. This is entirely my personal decision. I have had no such requests from my constituency association but I believe that it is the right and proper action to take. As regards the allegations of Channel 4 and the Daily Telegraph I find them contemptible and will not comment further at this time. Although I will retire from Parliament I shall continue my public and political life and am much looking forward to doing so over the years to come.”

UPDATE III: No. 10:

Number Ten say "understand" Sir Malcolm Rifkind's decision to stand down and pay tribute to his work as a Foreign and Defence Secretary

— norman smith (@BBCNormanS) February 24, 2015

UPDATE IV: 

Tories:

“Sir Malcolm has had a long career of distinguished service both to the Conservative Party and the country.  We respect and support his decision to stand down.”