New Zealand blocking refugees flying here on holiday visas - Nauru President

New Zealand has been accused of blocking refugees from travelling here on holiday visas, according to Nauru government officials.

But New Zealand's Government says all applications for visitor visas are assessed on a case-by-case basis.

According to The Australian, Nauru requested Pacific nations grant refugees on the island visas to travel. It came with a note from the UN advocating for their right to travel outside of the country they were processed in.

But Nauruan President Baron Waqa says New Zealand is still yet to agree to allow the Nauru refugees in on holiday visas, blocking entry to about 450 refugees. Only Fiji has allowed them to do so.

"Refugees, we encourage them to travel outside of Nauru but not to Australia," Mr Waqa told The Australian.

"But some have travelled to Fiji on visas. We give them a Nauru passport, a special passport. And so they are free to move around."

Former Australian immigration minister Amanda Vanstone told The Australian it seemed that New Zealand was protecting its borders.

"Welcome to our world," she said. "They obviously don't want their borders crashed either."

The New Zealand Government says all applications for visitor visas for New Zealand, including from refugees, are assessed on a case-by-case basis against standard criteria.

"In April 2016 the Government of Nauru sent a letter to all Pacific Island Forum countries requesting governments to recognise official refugee travel documents issued by Nauru as Nauruan passports," a spokesperson says.

"New Zealand recognises valid refugee travel documents, in line with UN obligations."