The Australian National University has also warned The Gods Cafe and Bar it will block access, shut off the water and power, dispose of cafe property left inside, and bill owner Jaye Min $120,000 for each day he overstays.

But the cafe's legal team, Kamy Saeedi Lawyers, has filed an urgent injunction in the ACT Supreme Court to prevent an on-campus showdown this week.

The popular coffee stop has been marked for demolition as part of the multi-million dollar Union Court redevelopment.

The ANU intends to commence work this week, which would include the erection of hoarding and disconnection of services to the site on Tuesday.

Cafe owner Mr Min has been told to clear out by July 3, despite signing a lease for the site until 2018, with the option to extend to 2023.

He says he will not leave the campus without a court order or a $650,000 payout.

Mr Min claims the university has not correctly terminated his lease and has no right to kick him out.

But the ANU argues it can cancel a lease at any time if it has an alternative use for the site, and the proposed Union Court redevelopment had been raised in December 2014.

The parties clashed in court earlier this month, but the matter remained unresolved after the most recent appearance in the ACT Magistrates Court last Thursday.

Mr Min has since pledged to open on Monday and give away free coffee.

But the university - through a letter from its lawyers - on Thursday threatened to physically remove the Gods from the ANU Arts Centre, block access, shut off services, dispose of the cafe property left inside.

The letter said the ANU intended to erect hoarding and disconnect services to the site on Tuesday.

It also said the university required vacant possession and expected any keys or access passes to be returned by Tuesday.

The ANU offered to allow Mr Min supervised access to collect personal items on Tuesday.

As the building is to be demolished, the university also offered to waive the usual legal requirements for tenants to "make good" and repair any damage upon departure.

"Should your clients or any other person wrongfully occupy the premises beyond 3 July 2017, thereby delaying the redevelopment works, any loss suffered by our client as a result will be pursued against [Mr Min] or any other trespasser," the letter said.

The ANU estimated it would cost $120,000 for each day the project was delayed.

"Should your clients fail to vacate the premises by 3 July 2017, we are instructed that [the ANU] will take such action that it considers necessary, including entering and recovering possession of the premises.

"Further … any property … that is not removed from the premises promptly by 3 July 2017 will, at the [university's] option, either become the property of [the ANU] after giving written notice to that effect or be disposed of by [the ANU] as they see fit (at your client's expense)."

The Gods Cafe proprietor Jaye Min said the ANU had resorted to aggressive tactics to cover its weak legal position.

He said his staff – many of whom are students – were scared for their safety and fearful for their future if they defied the university.

"The ANU has made a mistake by terminating my contract when they had no right and then withdrawing their case when we should have just let the courts look at it," Mr Min said.

"Now they want to fix those mistakes using aggression. The ANU claims to be part of the community but being part of the community means respecting the operation of the law and not having private security resolve the dispute for you.

"Despite knowing that the ANU does not have an eviction notice, my staff are scared for their safety if they try to show up to work this week.

"We employ a lot of students and it was already hard for them to be involved in a fight against the institution that holds their future in its hands."

The injunction is expected to be heard in the Supreme Court on Monday morning.