The potential expulsion of Russia's ambassador threatens to derail a legal battle over the country's new embassy in Canberra.
Russian government lawyers admit they're worried key figures could be booted out of Australia as they fight to hold onto their diplomatic headquarters.
They took their challenge to the Federal Court on Thursday, arguing local planning authorities didn't have the authority to terminate their Yarralumla lease.
Asked how long they would need to prepare important court documents, the lawyer representing Russia, Elliot Hyde, stressed the urgency of the matter, saying they were worried the people they took instructions from in Australia could soon be punted.
Justice Steven Rares agreed he was concerned if a central witness "who I presume is the ambassador" may be expelled.
"He is in the jurisdiction and I hope he remains so," Mr Hyde responded.
Russia is taking on the National Capital Authority, who recently declared the country had not met terms of an agreement to finish construction of its new embassy within three years of signing a binding land deal.
But in the Federal Court, Russia's lawyers argued they'd met the terms by completing construction on a single consular building, despite the greater embassy complex not being finished.
The case management hearing was told Russia was initially given 20 days to exit the embassy site, but Australia had agreed they could stay on the land until the court matter was finalised.
Australia's lawyer David Robertson said the agreement called for "a building" to be completed, but a single building within the embassy did not meet those terms.
Russia purchased the rights to the new Yarralumla site in 2008, intending to replace its existing embassy in Griffith.
Building approvals were agreed in 2011.
When announcing the lease termination in August, NCA chief executive Sally Barnes said the unfinished work detracted from the overall vibe of the area.
"With limited blocks currently available for diplomatic purposes, unless a country can demonstrate a willingness and ability to develop the site, the NCA supports a policy of 'use it or lose it'," she said.
The matter will return to court on November 18.
Earlier this week, Foreign Minister Penny Wong said expelling Russian ambassador Alexey Pavlovsky was "under consideration" after Vladimir Putin threatened to use nuclear weapons.
Dr Pavlovsky told the Nine Newspapers the move would be met with reciprocal actions from Moscow.
