An Australian lawyer who had been barred from leaving Mongolia has been cleared of involvement in a corruption case and will soon be able to leave the country, her employer said Monday.

SouthGobi Resources, a subsidiary of Anglo-Australian resources giant Rio Tinto, said Mongolia's Independent Authority Against Corruption (IAAC) had ended its questioning of its chief legal counsel Sarah Armstrong.

SouthGobi has been informed by the IAAC that the 32-year-old "is no longer a suspect in their investigations", the coal firm said in a statement to the Hong Kong stock exchange where it is listed.

"The IAAC has informed the company that she will shortly be able to leave the country," SouthGobi said.

The Australian was barred from boarding a flight from Ulan Bator to Hong Kong in October as Mongolian authorities probed a corruption case, triggering calls from Armstrong's mother to let her daughter return home.

Officials wanted to question Armstrong as a witness to alleged corruption and money-laundering, although details of the case have remained sketchy.

Mongolian officials said Armstrong was wanted over an investigation into the former chief of Mongolia's mining authority, who is suspected of illegally handling mining licences, according to Dow Jones Newswires.

Australian Foreign Minister Bob Carr refused to comment on the nature of the case when he confirmed in October the lawyer was barred from leaving Mongolia.

SouthGobi said the IAAC was continuining its probe into "the divestment of certain SouthGobi licences to third parties" and the "involvement and conduct of government officials" linked to the case.

It gave no other details.

Australia is the biggest investor in Mongolia's mining sector and the largest mine in the resource-rich country is backed by Australian money, according to Carr.