Whittaker, who started his banking career at Lazard in 2005 and then moved to fellow investment bank PJT in 2015, will re-join Lazard as a London-based managing director in its EMEA restructuring franchise.

The 45-year old Briton will work closely with David Burlison, who co-heads Lazard's EMEA restructuring practice, and Chris Mallon, who joined Lazard in April as a senior adviser.

"One of the many benefits of having Sam back is that he has an extensive network of relationships with banks, hedge funds and lawyers which clearly is a big plus for us," Burlison told Reuters.

The U.S. bank, which leads Refinitiv's league tables for this year's global restructurings ahead of PJT Partners and Houlihan Lokey, has also hired James Simpson as a director in October as part of a push to win business on behalf of companies with liquidity issues and their creditors.

Independent advisory firms with restructuring capability, such as Lazard and Houlihan Lokey, are in high demand as boardrooms seek to limit the damage of a new wave of lockdowns across Europe.

"The second wave of coronavirus has made capital requirements even more acute and exacerbated the need for a comprehensive debt restructuring," Burlison said.

"As household disposable income is increasingly reduced through the course of the pandemic, more companies are likely to run into trouble," he added.

Lazard's restructuring pipeline this year has been equally split between advising companies and their lenders.

It has handled complex negotiations involving energy companies such as oil and gas producer Premier Oil and offshore oil drillers Valaris and Seadrill as well as hospital operator NMC Health.

The 172-year old bank - founded in New Orleans by French brothers Alexandre, Lazare and Simon Lazard as a dry goods merchant dubbed Lazard Frères & Co - is also close to a number of European companies, such as Spanish renewable energy firm Abengoa, that have used Chapter 11 in the United States as a conduit for restructuring their debt.

Burlison said restructuring mandates are the result of cooperation between various parts of the bank, including debt and equity capital markets as well as M&A advisory.

"We all work in unison to provide a full spectrum of solutions to clients facing difficult times or periods of stress," he said.

(Reporting by Pamela Barbaglia in London; editing by Barbara Lewis)

By Pamela Barbaglia