Immigration New Zealand has expressed concern about the way Go Bus has recruited migrant workers.
This comes amid accusations the company has abused immigration rules and as the Tramways Union and the Labour Party have called on Ngai Tahu, as Go Bus's majority shareholder, to be a more socially responsible business owner.
INZ said it had been monitoring the number of workers Go Bus was employing from offshore and last year 35% of its drivers were on work visas.
Go Bus South Island operations director Nigel Piper disputed the 35% figure provided by INZ and ''absolutely'' rejected any suggestion it had attempted to circumvent immigration processes.
INZ area manager Darren Calder said it had been monitoring the number of workers Go Bus was bringing in from offshore and wrote to the company last June expressing concern about how it was recruiting the workers.
In the letter it noted the need for the company to apply for approval in principle (AIP) to bring in workers from off-shore given it had provided job offers for nearly 130 essential skills work visa applications in the previous four years.
''INZ expressed its concern about the company's decision not to apply for an AIP as recruiting migrant workers one by one could be seen as an attempt to circumvent the relevant immigration instructions and affect the labour market.''
Companies could apply for AIPs to recruit a specified number of overseas workers over a certain period of time, as long as they could demonstrate that they cannot find suitable workers in New Zealand.
It met the company in December last year to discuss the option of applying for an AIP, but the company declined, saying it had no plans to bring in large numbers of drivers from offshore.
At the time, about 35% of Go Bus' drivers were on work visas.
Tramways Union national secretary Kevin O'Sullivan said he received a call from an INZ official from Dubai about two months ago, who said INZ was concerned about the way Go Bus was recruiting workers from the Middle East and was going to ''put a stop to it''.
''What the fella told me was that when the people apply for a job from those countries they have got to apply individually, but Go Bus was apparently making bulk applications, which is against the rules.''
He repeated the accusation Go Bus employed people from offshore as part of efforts to suppress wages and conditions and called for majority shareholder Ngai Tahu to improve conditions and employ more Maori people.
''They should actually be doing a lot more to help local people.''
A Go Bus worker, who wished to remain anonymous, said a Fijian Indian staff member was shifted to its Christchurch operation after his visa was declined because he was not earning enough in Dunedin.
After his visa was accepted in Christchurch, where staff were paid more, he was shifted back to Dunedin about a month ago.
INZ declined to comment on the accusation, saying it was ''not possible to discuss individual cases without a privacy waiver''.
It also did not respond to questions about Mr O'Sullivan's call from an INZ official.
Mr Piper rejected accusations it had acted improperly.
''We absolutely reject any suggestion that Go Bus has or is attempting to circumvent immigration processes.
''We discussed the AIP requirement during the recruitment for Christchurch with the local INZ staff and they confirmed that it would not be necessary at that time.''
Asked about the 35% figure provided by INZ, he said its own records showed that out of more than 2000 staff it employed nationally, fewer than 100 were on work visas, which equated to 4.7% of its workforce.
''Of that number 76 are based in Christchurch and were employed post the quake, due to severe labour shortages.''
He would not comment on the accusation about the Fijian Indian worker, saying: ''We are not prepared comment on individuals.''
Labour Party workplace relations and immigration spokesman Iain Lees-Galloway said Ngai Tahu had a responsibility to be an exemplar employer and to ''use their investments to provide opportunities to their people''.
''In this instance they have done none of that,'' Mr Lees-Galloway said.
Ngai Tahu said no-one was available to respond to questions yesterday.
