London | The chief executive of Royal Bank of Scotland, Ross McEwan, is quitting after five and a half  years in charge, potentially putting him in the frame for the top job at National Australia Bank.

The 61-year-old New Zealander has been touted as a possible contender to fill the role left vacant after Andrew Thorburn resigned in the wake of the Hayne Royal Commission's coruscating review of the top NAB executives' performance.