CANBERRA, Australia (AP) — Australia hopes to send thousands of Iranian asylum seekers back to their homeland under a new deal with Tehran, Australian officials said Wednesday.

Foreign Minister Julie Bishop's negotiations with her Iranian counterpart Javad Zarif were well advanced on a deal expected to be signed next week that would lift Tehran's long-standing refusal to accept Iranian asylum seekers who don't want to come home, Bishop's office said.

"Our preference is for people not owed protection to return voluntarily. However, where people do not have a legal basis to remain, they may be subject to deportation," Bishop's office said in a statement.

Negotiations began after Bishop visited Tehran in April last year and agreed to start a formal dialogue with Iran on a range of issues, including cooperation to prevent people smuggling, the statement said.

Under the repatriation agreement expected to be signed by Zarif when he visits the Australian capital Canberra on Tuesday, Australia would demand guarantees from Iran that Iranians who returned home would not be persecuted or punished.

The Iranian policy change could cover almost 9,000 Iranian asylum seekers. About 400 were in Australian-funded immigration centers on the Pacific island nations of Nauru and Papua New Guinea.

But most live in the Australian community. It is not clear how many of them are genuine refugees who could not be sent back to Iran, but Australia regards the majority of asylum seekers from Iran to be economic migrants rather than refugees.

They have been left with uncertain futures, with Australia refusing to resettle them and Iran refusing to take them back.

An Iranian refugee couple who resettled in Cambodia under an expensive program funded by Australia to keep asylum-seekers from its soil returned to their homeland in February, Cambodian and Australian officials said.

Gen. Tan Sovichea, head of the refugee office in Cambodia's Interior Ministry, said five bona fide refugees had resettled in Cambodia from Nauru under a four-year, 55 million Australian dollar ($41 million) program financed by Australia.

"The Iranian couple told us that they decided to go back to Iran after they felt homesick," Tan Sovichea said.

Last October, one of two ethnic Rohingya men resettled under the deal went home to Myanmar, leaving only an Iranian and another Rohingya in Cambodia. Tan Sovichea said they appeared to be happy with their new lives.

The new Australian deal with Iran would reflect Tehran's determination to improve its economic and diplomatic relations with the West in the wake of last year's landmark international nuclear agreement which removed sanctions.