Iron-ore's plunge has put Western Australia state's credit rating under pressure, but that's not likely to imperil Australia's AAA rating just yet, analysts said.

"Undoubtedly, Australia's fiscal position has weakened over the past year, and the May Budget will almost certainly reveal upward revisions to forecast budget deficits, and consequently government debt," analysts at ANZ said in a note Thursday. But it added, "Despite the deterioration in the fiscal outlook, current forecasts suggest that net government debt is unlikely to hit levels that could threaten Australia's sovereign credit rating."