Walsh Perth 060801 AFR pic by Erin Jonasson, CEO of Rio Tinto Sam Walsh and Gina Rinehart, from Hope downs, at the CEDA lunch today held at the hyatt

Gina Rinehart and Sam Walsh. Photo: Erin Jonasson

GINA Rinehart has urged the new boss of Rio Tinto to fast-track several more iron ore projects in the Pilbara that would reinforce her family's long-standing relationship with the company.

Sam Walsh was appointed as chief executive of Rio Tinto only on Thursday, after the sacking of Tom Albanese, but already has a long list of suggestions from Mrs Rinehart, who issued a statement on Sunday expressing her disappointment that such a ''reasonable and straight-forward person to deal with'' had been replaced.

But Mrs Rinehart is also well acquainted with Mr Walsh, who has spent much of the past decade living in Mrs Rinehart's native Perth, managing Rio's iron ore portfolio.

That portfolio includes the Hope Downs joint venture with Mrs Rinehart's Hancock Prospecting, and she urged Mr Walsh to approve swiftly further mines within the Hope Downs precinct.

"By far Rio Tinto's best investment in the last decade has been in Hope Downs, which Sam Walsh was intimately involved in. We look forward to Sam providing the leadership and adding to the great success Hope Downs has been for the Rio Tinto group by committing to develop other Hope Downs resources in a timely manner,'' she said in the statement.

Hope Downs contains six iron ore deposits of which two are mined under a 50:50 joint venture between Rio and Hancock.

Statistics released last week showed the joint venture produced just over 30 million tonnes of iron ore in 2012, and that will soon be doubled when a third mine at Hope Downs comes into production this year.

Mrs Rinehart described three other iron ore assets in the Hope Downs precinct - Baby Hope, Hope 2, and Hope 5 - as being ''convenient for early development'' and urged Mr Walsh to proceed with them in a timely fashion.

"Now that the underutilised Lang Hancock Railway is in place, such developments would also offer substantial synergies to the existing adjacent Hope Downs mines,'' she said.

Iron ore is by far Rio's biggest money spinner, having delivered close to 80 per cent of the company's revenue in recent years.

Amid a list of suggestions, Mrs Rinehart also urged Mr Walsh to lobby the Australian government to remove its taxes on mining and carbon, and to shift Rio's headquarters from London to Perth.

''We have urged him to take this opportunity and also move the Rio Tinto headquarters from London to Perth, where, given most of Rio Tinto's revenue is generated in Australia, it logically belongs,'' she said.

Rio's roots have been in London since 1873, when a group of British investors formed a company to develop ancient copper mines in Spain near a river named ''Rio Tinto''. The company has always managed a vast global empire from London - albeit with a corporate office in Melbourne - and has its biggest growth project in Mongolia.

Meanwhile, global credit ratings agencies have said they are prepared to look through the current management turnover and $US14 billion worth of write-downs at Rio Tinto and leave its rating unaffected by the turmoil.

Problems around Rio Tinto's foray into aluminium triggered a rash of credit rating downgrades for the miner in late 2008, pushing up its cost of debt as it lost its prized ''A'' rating.

Credit ratings agency Fitch, which was the first to issue a downgrade in 2008, said Rio Tinto's latest write-down will not affect its ''A-'' long-term rating.

The charges - which were mostly related to Rio's aluminium unit Alcan as well as $US3 billion related to its coal project in Mozambique - were non-cash and the company's real strength was in its iron ore business, which continued to see record output, Fitch said.

Moody's also said Rio's ''A3'' rating was unaffected.

UBS analyst Glyn Lawcock said Mr Walsh was seen as a ''logical successor'' given his two decades at Rio Tinto.