Dentons has delayed voting on its proposed merger with US outfit McKenna Long & Aldridge, blaming a lag in the due diligence process.

The firms had earlier planned to complete all voting "no later" than 14 November, after both boards had given the green light to the tie-up.

It had initially been thought the merger would go through in October. No new date has been set for the conclusion of the proposed deal. 

In a statement, Dentons said: "The process for consideration by the partnerships of Dentons and McKenna Long & Aldridge of a potential combination is ongoing and the period of partner review not completed.

"It would be premature to share further information until all partnership entities of both firms have concluded their respective processes."

This time last year, partners at Dentons legacy firm SNR Denton voted through a three-way tie-up with Salans and Canada's Fraser Milner Casgrain.

The news of the delay comes as Dentons' former chief executive Howard Morris has resurfaced at Morrison & Foerster's London office, after resigning from his previous firm in September.

Morris – who joins as senior of counsel and head of MoFo's business restructuring and insolvency practice in London – was most recently responsible for Dentons' global integration and client development.

At MoFo, Morris will focus on cross-border and pan-European transactions and insolvency proceedings.

In the US, MoFo has a strong restructuring and insolvency practice, having advised real estate finance company Residential Capital in its chapter 11 proceedings in 2012, as well as acting for MF Global's trustee in 2011.

"The addition of Howard comes at a crucial time with significant levels of corporate debt still to be restructured across the UK and more widely in Europe," commented Gary Lee, chair of the firm's business restructuring practice.

"His experience and track record make him the ideal individual to head this group in London. Distressed investors are increasingly looking for opportunities in Europe and this appointment demonstrates our continued commitment to our clients in this area."

Originally a banking and finance lawyer with a practice focus on corporate recovery and insolvency, Morris headed legacy Denton Wilde Sapte from December 2004, when he replaced Virginia Glastonbury in the role of chief executive.

Following his re-appointment in an uncontested election in 2007, Morris helped drive the merger of Denton Wilde Sapte and Sonnenschein Nath & Rosenthal, and initially shared the role of chief executive at merged firm SNR Denton with current CEO Elliott Portnoy.

In 2011 Morris was transferred to New York and made responsible for knitting together SNR Denton's offices and selling the merged firm to clients.

Prior to joining Dentons, Morris worked at Allen & Overy and practiced as a barrister for more than six years.

"Howard is a superb addition to the firm in London and his arrival gives a significant boost to our global restructuring capabilities," added London managing partner Trevor James.