In an interview with the Financial Times, Mr Agius said there needed to be a level playing field in the global financial system.
He voiced his worries that proposed G20 regulations on bonuses were open to different interpretations.
The US Federal Reserve has already indicated that it sees one of the G20 proposals, that around half of banking bonuses should be deferred, as an example rather than a binding proposition.
Mr Agius also said he was concerned that proprietary trading had been demonised.
"If excessive risk is taken out of the system, that's good," he said.
"But we have to be very careful where we draw the line."
Barclays is on track to announce record annual profits of more than $16 billion for 2009, according to media reports.
By Gary Cooper