Scheduling requirements were still being worked through, although Palmerston North District Court would be used, he said.
The building was not old. It was officially opened by then Prime Minister John Key in 2010. While it met current standards, the Ministry had asked an engineering firm to assess the building against proposed new guidelines for concrete buildings.
Engineering firm WSP Opus concluded that part of the building did not meet those standards. The cost of repairs was not known at this stage.
Crafar said a decision was made to close as quickly as possible to speed up the strengthening work and reduce risk to the building's occupants.
Ministry of Justice was committed to the health and safety of all people who work in or visit its facilities throughout New Zealand, he said.
"For the safety of our staff and other court participants, we have chosen to close the court while work to increase the strength of some connections between a floor slab and some steel beams is undertaken."
"I recognise that this will cause significant disruption to court participants in Levin and we are doing all we can to minimise this...changing venues and times for court hearings. If you are affected, a Ministry staff member will be in touch."
Crafar said planning was underway for the construction work and although there was no known reopening date yet, the work was estimated to take at least four months.
"We have not released a reopening date as we are still working completing the design work, obtaining any required consents and engaging a construction company to undertake the earthquake strengthening works," he said.
"Once the courthouse is closed, we will be focused on additional testing and completion of design work and the logistics of relocation such as transporting files. We anticipate construction will be underway in the next few weeks."
Crafar said Ministry of Justice managed a significant property portfolio, one of the largest in the public sector, with more than 100 operations in 95 locations.
It had a routine programme of assessment and maintenance work for those buildings, he said.