China's Sinosteel Corp has again extended its A$1.36 billion (US$1.29 billion) takeover offer for Australian iron ore prospector Midwest Corp by another month, as it seeks acceptances from more shareholders.

The offer will now close at 7pm Sydney time on August 25, Sinosteel, which now has a 54.16-percent holding in Midwest, said in a regulatory filing last Friday.

Sinosteel needs 90 percent in order to force minority shareholders to sell, according to Australian securities rules. Sinosteel had extended the offer by one week last Friday, when it was originally due to close.