New Zealand's opposition Labour party says the new ferry that links Tokelau to Samoa may not be fit for purpose.
The Mataliki was built in Bangladesh under commission from the New Zealand government and delivered to Tokelau in February.
The Labour party's foreign affairs spokesperson David Shearer said the ferry failed its original sea trials and has been built over its designed weight.
"It certainly won't be as efficient in terms of being able to carry the passenger numbers and the cargo as was originally intended," he said.
"My understanding is because of that there is a very probable likelihood that they will have to continue to run additional cargo boats at the cost of about 10 thousand dollars a day up to Tokelau to meet the balance."
David Shearer said the ferry would not provide passage to Niue as was originally intended.
The shipping magazine Skipper reports that the Mataliki can carry 60 passengers and 20 tonnes of cargo.
It says the ferry was built with non-specified recycled steel, adding an estimated 60 tonnes to its weight.