New Zealand has postponed its phased border re-opening plans until the end of February over concerns of the rapid global spread of the Omicron variant of the coronavirus, Reuters reports.

Non-quarantine travel, which was to have opened for New Zealanders in Australia from January 16, will be pushed back until the end of February, Covid-19 Response Minister Chris Hipkins said at a press conference in Wellington.

"All of the evidence so far points to Omicron being the most transmissible Covid-19 variant yet. There's no doubt this is disappointing and will upset many holiday plans, but it's important to set these changes out clearly today so they can have time to consider those plans," he said.