The staff poaching and counter-poaching between UBS and Bank of America Merrill Lynch that has enthralled London's financial community reached new heights on Wednesday when 17-year UBS veteran Alex Wilmot-Sitwell defected to the US bank.

Wilmot-Sitwell, 51, will be joining BofA Merrill in the coming months as president of Europe and Emerging Markets, excluding Asia.

That job was originally earmarked for top BofA Merrill dealmaker Andrea Orcel, who barely a month ago jumped ship to UBS to co-head its investment bank with Carsten Kengeter - a role Wilmot-Sitwell once held.

Alex and Andrea are both big beasts, said one BofA Merrill banker, adding that the collective view is that this is a good hire for Bank of America.

Wilmot Sitwell was a senior figure at UBS, though he was recently stripped of some operational responsibilities when he moved into the role of chairman of the investment bank around the time that news of Orcel's impending arrival emerged.

He also ceased to be a member of the UBS executive board.

Orcel shunned the BofA Merrill promotion to join forces with former colleague Sergio Ermotti, the UBS chief executive who is leading a revamp of the investment bank after a string of setbacks.

The moves by Wilmot-Sitwell and Orcel, both veterans of their respective banks, are symptomatic of major upheaval across the investment banking industry, which is being squeezed by tough new regulations and rocky markets.

As well as hiring Orcel - an architect of some of Europe's biggest European mergers and acquisitions - UBS has taken on six more heavyweight bankers from BofA Merrill, signalling an emphasis on the advisory side of the business, at a time when the Swiss bank's trading activities are being scaled down.

UBS declined to comment.

PROLIFIC DEALMAKERS

Wilmot-Sitwell had until recently been a key figure for UBS in Asia Pacific, which he went to run for the bank about 18 months ago, partly to steady the business after a series of departures.

Like Orcel, famed for his extensive contact book, Wilmot-Sitwell is a key dealmaker. UBS has previously showcased his involvement in transactions for big companies such as miner Anglo American and airline British Airways.

His move, announced in an internal memo on Wednesday, will see him return to London and report to Tom Montag, BofA Merrill's co-chief operating officer.

Montag praised Wilmot-Sitwell's management experience and tremendous global insight, a view echoed by other BofA Merrill insiders.

Wilmot-Sitwell will be responsible for driving a more integrated strategy across Europe and emerging markets. This was previously managed separately by Orcel and Jonathan Moulds, who will be retiring this year.

Orcel, a prolific fee-earner, had not been given top managerial roles at BofA Merrill, though he was asked to add Moulds' job to his responsibilities just before he left for UBS.

BofA Merrill has also made other raids on UBS staff, particularly in Asia Pacific, where the Swiss bank is a top fee earner. A year ago it brought in Matthew Koder, now president for that region.

Koder has since brought over other key bankers from UBS in the region, including equities specialist James Fleming.

(Additional reporting by Sophie Sassard in London and Lawrence White in Hong Kong.; Editing Helen Massy-Beresford and Jane Merriman)