The board of United Continental Holdings Inc. said Monday it will nominate a new chairman from within its ranks after veteran industry executive Robert Milton opted to leave the third-largest U.S. carrier.

Total compensation for Chief Executive Oscar Munoz is also set to almost halve for 2017 compared with the previous year as the airline continues efforts to recover from a series of problems with passengers and investors.

Milton was appointed two years ago with the backing of two activist shareholders pressing for reform at Chicago-based United , which has continued to challenge investors with a series of management and operational missteps.

The latest move, disclosed in United’s proxy, isn’t expected to presage any move to replace Munoz, according to people familiar with the situation. Munoz’s total compensation almost halved to $9.56 million last year from $18.7 million in 2016.

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United CEO takes pay cut, board seeks new chairman from within