Optus parent company Singtel, an international telecommunications conglomerate headquartered in Singapore, told its local stock exchange on Friday that Optus was communicating the government advice to customers.

Late last month, when the government was riding a wave of consumer anger over the hack in which online criminals accessed data on almost 10 million current and former customers, Prime Minister Anthony Albanese and Foreign Minister Penny Wong demanded Optus cover the cost of passport replacements.

“They will cover the costs of replacing affected customers’ passports,” Albanese said at the time. “I think that is entirely appropriate.”

A survey from around that time, conducted by Resolve Strategic for The Sydney Morning Herald and The Age, found 84 per cent of respondents believed Optus should pay to reissue Medicare cards, passports and other identification documents when personal details had been released.

The passport office now emphasises that it is experiencing very high demand for passports and some are not being processed within six weeks. “If you’re planning to travel soon, don’t apply for a replacement,” it advises. “We can’t guarantee you’ll get your new passport in time for your trip.”

A spokesman for the Department of Foreign Affairs and Trade said affected customers may still wish to have their documents replaced and should contact Optus for information about reimbursement.

In a statement, an Optus spokeswoman reiterated the government advice and thanked a string of government departments and agencies, including the passport office, for their collaboration.

“If impacted customers still want to change those documents, Optus is establishing a process to reimburse them,” the spokeswoman said.

Optus confirmed to The Sydney Morning Herald and The Age last week that about 150,000 passport numbers were accessed in the hack, though a significant portion were expired. The departmental spokesman said Optus had advised it about 100,000 passports were affected.

Replacing a passport that is valid for at least two years costs $193 and retains its existing expiry. Passports with less than two years remaining can be replaced with a new one that lasts for a decade at a cost of $308.

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