Irwin Mitchell has lost its place on energy giant National Grid's legal panel as part of an ongoing review by UK general counsel and company secretary Karen Clayton.

The firm, which won a first-time appointment to the UK panel in 2011 to advise purely on debt recovery matters, has not been reappointed as part of a review of the company's existing panel firms.

Shakespeares, which already advises National Grid on property work, will instead take over from Irwin Mitchell having been awarded a one year place.

In addition to a review of the current panel line-up, which will take effect for the coming year, Clayton is also overseeing a wider review, which will take effect from April 2015 and is open to non panel firms.

National Grid's panel currently comprises Allen & Overy and Linklaters as the company's main corporate advisers, while Berwin Leighton Paisner, CMS Cameron McKenna and Eversheds all hold spots to advise on commercial, construction and disputes work.

The remaining firms include Irwin Mitchell, Dundas & Wilson, SGH Martineau, Dentons, Walker Morris, Squire Sanders, Bircham Dyson Bell, Brook Street des Roches, Field Fisher Waterhouse, DLA Piper and Needham & James.

A statement from Irwin Mitchell reads: "Irwin Mitchell is a strong, growing business which has recruited more than 30 experts into partner-level positions in the past 15 months, completed five acquisitions and exceeded £200m in income for the first time in 2012-13. We are of course disappointed with National Grid's decision but our business legal services team is continuing to expand and recently it has won work from a number of significant new clients.

"Irwin Mitchell has also been re-appointed by a number of existing clients following formal tender processes which again shows the strength of our commercial division and our ability to provide innovative legal solutions."

Clayton, who took on the role in 2009, reports to group general counsel Alison Kay.