The series, which was to include a much-anticipated rematch between Tonga and New Zealand and other tests involving Samoa, PNG and the Cook Islands was originally scheduled for June.
However the Asia Pacific Rugby League Confederation said it was now looking at delivering fixtures in October and November.
Deputy Chair Greg Peters said the unprecedented measures had to be taken for the safety and well-being of players, staff and supporters.
"With the recent announcement on mass gatherings and the unpredictability of this pandemic, the safety and well-being of our players, staff and supporters remain a priority," he said.
"We are also very conscious of the current demand on some of our players due to the travel restrictions in place which we will be taking into full consideration going forward."
Peters admitted that even if restrictions were lifted before the event date, it would not be feasible to undertake the work required to deliver the June tests.
"The best-case scenario is our calendar is postponed, depending on what the NRL season looks like the back end of the year, but of course, we cannot guarantee anything at this stage."
"We are in unfamiliar and unknown territory; collectively, we are all feeling the widespread impact of this pandemic but rest assured, we will be exploring every possible option," Peters said.
Chairman Sandis Tsaka said there were still hopes all nations would be able to play at least once this year.
"We're going with a Plan B where we are putting all the Oceania Cup matches towards the end of the year.
"Obviously that would require a lot of discussion between the NRL and the Super League around how they would structure their seasons going forward," he said.
"We will need to see whether we are struggling with the State of Origin, the NRL and Super League matches because the Oceania Cup is mostly made up of players competing in those competitions so we'll be liaising with them to find an appropriate time within the calendar towards the end of the year around November but obviously everyday the situation is evolving."