Vice UK has been accused of an “old-fashioned union-busting ruse” by the head of the National Union of Journalists after the web-based company rejected a push for recognition from staff.

The NUJ general secretary, Michelle Stanistreet, also said Vice’s claims the union had shown a “concerning lack of transparency” in negotiations were untrue and vowed to continue pushing for recognition.

Vice had offered to set up an internal committee rather than recognise a union for its staff members. “Rejecting calls for union recognition from their own journalists and then trying to fob them off with a Rupert Murdoch-style staff association is a pretty old-fashioned union-busting ruse that misses the point,” said Stanistreet in a statement. “It’s a shame that the company has proven so resistant to listening to its own staff and facilitating what they want: a collective voice at work.”

Stanistreet also hit back at Vice’s suggestion in an email to staff that the NUJ was not equipped to represent staff at “innovative, digital workplaces” where employees regularly worked across departments and switched jobs. She described the suggestion as laughable.

Vice has said it has not seen enough evidence of widespread support for the union to agree to recognition “at this point”, but said it would reverse its decision if an official arbitrator ruled there was a high level of backing.

The dispute over transparency appears to centre around the NUJ’s refusal to provide a breakdown of numbers of supporters directly to Vice, which the union feels could be used to identify individuals. The union believes any checking of support should be done through an independent arbitration service. Vice countered that it cannot assess whether support for recognition is widespread without the information.

Stanistreet said the NUJ would now pursue the case through legal channels to make Vice recognise the union. She said: “If the company wants that to be gained through the law forcing their hand rather than through sensible engagement with their staff, so be it.”

A Vice staffer involved in the push for recognition who asked not to be named said recent improvements to conditions at Vice were welcome, but union recognition was still necessary. The staffer said: “The benefits that have been publicised such as competitive salaries, a pension scheme and so on are long overdue and we’re pleased the management feels the need to treat workers more fairly thanks to our efforts. This makes us more determined to continue pushing for what staff want, which is a recognised trade union, not a staff association imposed from above. Our colleagues in the US office – as well as other new media companies – have this, and we deserve it too.”