Downer writes an open letter protesting against Solomons' AG appointment.
The letter has been published in last Friday's issue of the local daily, the Solomon Star. This is the second time Mr Downer had written an open letter to the people of Solomon Islands.
The first was in September last year after the expulsion from Honiara, of Australia's former High Commissioner Patrick Cole.
Radio Australia says in the Solomon Star letter, Mr Downer expresses Australia's strong objection to the swearing in, saying Mr Moti's appointment is a large backward step for governance in Solomon Islands.
He says Australia will be watching very carefully any actions taken by the new attorney-general.
Mr Downer says these will include moves which could affect the ability of the Australian-led Regional Assistance Mission to Solomon Islands to work effectively and independently for the benefit of locals.
Australia wants to extradite Mr Moti, who was sworn into the position last week, to face child sex charges.
Mr Moti maintains his innocence.