Papua New Guinea has banned Australians from travelling to the Autonomous Region of Bougainville, following Canberra's announcement of plans to open a new diplomatic mission on the island.

Bougainville is an autonomous part of PNG, but will be holding a referendum in the next five years to consider independence.

Island-wide elections are currently underway to elect a government that will negotiate the date and wording of the referendum question.

The timing of Australia's announcement of the new diplomatic post angered the PNG government, with foreign minister Rimbink Pato calling the move "outrageous" and "mischievous".

The diplomatic response has been swift.

"I have instructed the chief migration officer to impose the ban with immediate effect and to notify all PNG Overseas Missions and Posts and domestic carriers of the ban," Minister Pato said in a statement released today.

"All diplomatic and foreign government officials wishing to visit Bougainville must seek clearance from the Department of Foreign Affairs before travelling," he said.

The ban will apply to tourist, business and other short-term entry visas, but not to work and permanent visa holders.

PNG prime minister Peter O'Neill said he was "shocked" to learn of Australia's plans for a new diplomatic mission.

However, Foreign Minister Julie Bishop has previously denied there had been a failure to consult saying the matter was discussed with Papua New Guinea last year and formally communicated before last week's budget.

Ms Bishop said a senior DFAT official will be sent to PNG to continue discussions about the mission.

"I look forward to further high-level engagement with my PNG counterparts at the PALM7 meeting in Japan later this week," she said in a statement.

"Our overseas development assistance in 2015-16 is estimated to be $477.3 million.

"This includes approximately $50 million directly earmarked for the autonomous Bougainville government to promote economic development."

The new mission in Bougainville's capital Buka was one of five new posts announced in the budget, including Doha in Qatar, Makassar in Indonesia, Ulaanbaatar in Mongolia and Phuket in Thailand.

PNG has consulates in Sydney, Brisbane and Cairns.