ZURICH (Reuters) -UBS said on Thursday it would split its top wealth management role as part of a shake-up of the Swiss bank's executive board that also sees new heads of its investment bank.

Rob Karofsky will become head of the Americas and co-president of global wealth management with Iqbal Khan, who will take charge of the Asia-Pacific region.

Khan will relocate to Asia to assume the new role from Sept. 1. Khan and Karofsky are seen as candidates to succeed UBS CEO Sergio Ermotti when he steps down, an event the bank has indicated could take place by early 2027.

The bank also named George Athanasopoulos and Marco Valla investment bank co-presidents, part of a series of changes UBS is putting into effect from July 1.

UBS, which is in the midst of integrating its longtime rival, Credit Suisse, made the announcements ahead of the merger of the banks' main parent companies, scheduled to be legally completed on Friday. UBS acquired Credit Suisse last year.

The parent merger is expected to allow the Swiss bank to get started with trickier stages of the integration such as combining IT systems, migrating clients from Credit Suisse and cutting the enlarged banks' workforce of more than 110,000.

As part of the rejig, former Credit Suisse CEO Ulrich Koerner will retire from the bank later this year, UBS said.

Ermotti said in a statement the new appointments put "even more emphasis on our long-term priorities and growth prospects, particularly in the Americas and Asia-Pacific".

"Our goal is to really increase dramatically the chances that we can have an internal candidate," Ermotti told Reuters last month in an interview.

According to a recent media report, Ermotti has rejected appointing an outsider as successor and intends to present internal candidates as he did when he last left UBS in 2020.

Vontobel analyst Andreas Venditti described the reshuffle as more far-reaching than expected.

"With these changes, Iqbal and Rob are the prime candidates for UBS's CEO job," he said.

Damian Vogel will take over the risk officer role from Christian Bluhm as part of a previously announced exit. Bluhm will remain in an advisory capacity.

The president of UBS Americas, Naureen Hassan, is to step down effective July 1, one of a string of female executives who have left the bank in the last year.

(Reporting by Noele Illien; Editing by Dave Graham, Muralikumar Anantharaman and Emelia Sithole-Matarise)