Federal Labor has labelled a government move to end the term of Mike Rann as Australia's high commissioner in London and replace him with Alexander Downer, as "blatantly political".
The coalition is reportedly planning to cut short the tenure of the former South Australian Labor premier in favour of Mr Downer, an ex-Howard government minister.
Fairfax Media says the federal government was hoping to keep the switch under wraps until after the SA state election in mid-March.
Deputy opposition leader Tanya Plibersek says it is a "blatantly political move".
"If the reports are accurate, the Foreign Minister Julie Bishop needs to explain why she would so abruptly install Alexander Downer as high commissioner - other than the fact he is a member of the Liberal party," she said in a statement on Tuesday.
Last week, the government announced Howard government finance minister Nick Minchin as Australia's consul general to New York after it removed former Labor state premier Steve Bracks' from the job.