Agius, who served as the Barclays chairman for the past six years, would stay in his position until a succession plan is in place.
Global rating agency Moody's said the decision to change the outlook on 'Barclays's C-/ baa2 standalone rating to negative from stable' reflects concerns over resignations of seniors and the consequent uncertainty surrounding the firm's direction, which are negative for bondholders.
Barclays Plc on Tuesday said its chief executive officer Bob Diamond has resigned with immediate effect after increasing pressure to step down following global interest rate manipulation scandal.
Barclays chairman Marcus Agius and chief executive Bob Diamond have resigned after regulators in the UK and US slapped a 290 million pound penalty on the bank.