Bus drivers on Auckland's biggest network will head to mediation in two weeks after failing to reach an agreement in two days of negotiations.
The Auckland Tramways Union and First Union, which represent drivers employed by Nz Bus, returned to negotiations on Thursday and Friday after 96 per cent of drivers rejected a collective contract offer a week ago.
The major issues had included the size of the drivers' pay rise and the start date of the contract to replace the existing collective, which expired this month.
First Union transport and logistics secretary Karl Andersen says some progress was made on ancillary aspects of the agreement, but nothing had been agreed on the wage rate and the term of the collective.
Mr Andersen says the two parties would attend mediation on July 23 and 24.
NZ Bus has offered a pay rise of 2.3 per cent from November and another 2.3 per cent from November 2013.
The drivers are seeking rises totalling between 7.2 per cent and 8.3 per cent over two years, and for it to take effect from the end of the present collective.
NZ Bus last week said it was confident an agreement would be reached without any industrial action.
NZ Bus, a subsidiary of Infratil, runs about 70 per cent of Auckland's buses, including the North Star, Go West, Metrolink, City Link, Outer Link and Waka Pacific buses.
The negotiations come three years after NZ Bus services were seriously interrupted during a contract dispute.