Senator Faulkner conceded yesterday he was ''right at the bottom of a steep learning curve'' after replacing Joel Fitzgibbon who resigned over a breach of the ministerial code of conduct.

The long-serving senator had a ''tough job ahead of him'', according to Mr Rudd who would make ''further announcements concerning changes to the executive in coming days''.

Senator Faulkner was cabinet secretary and Special Minister of State, responsible for enforcing the ministerial code of conduct, before he was moved to the Defence portfolio.

His appointment has been widely welcomed and Mr Rudd joked he had already earned a new nickname; Field Marshall Faulkner.

''Senator Faulkner is a man of great character and of great integrity and one of the most experienced and accomplished ministers in cabinet,'' Mr Rudd said.

''Beyond that, John Faulkner is a man of unquestionable integrity and strength of character and that has been reflected in the multiple portfolios he has been responsible for both in government and opposition over a long ... career.''

Senator Faulkner looked forward to rolling out reforms outlined in the Defence White Paper but would immediately focus on operations in Afghanistan and this region.

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