Auckland commuters could be in for trying times as bus drivers respond to a pay offer that has failed to win approval from union negotiators.

NZ Bus is urging passengers to make alternative travel arrangements between 9am and 2.30pm on Thursday, when all its Auckland buses, apart from those on the Inner Link route, will be off the road. More than 800 drivers are stopping work to vote on the offer.

According to a notice to the drivers of a paid stop-work meeting at Alexandra Park Raceway, issued by the Tramways Union and the First Union, eight days of pay talks with the company have ended without agreement for a new employment deal.

Auckland Tramways president Gary Froggatt, the unions' advocate, has confirmed his team is not ready to recommend a company pay proposal to the drivers, but said NZ Bus had accepted an invitation to present its position to Thursday's meeting.


He believed there remained scope for a settlement without extra disruption to passengers, possibly with the assistance of a Labour Department mediator.

But a long-term agreement reached in late 2009 after a bitter six-month dispute - which included the suspension of all NZ Bus services during a seven-day lockout of the drivers - is due to expire at the end of this week.

That will make it lawful for either party to take industrial action to press its negotiating position.

The agreement was aimed at ensuring there could be no industrial disruption to NZ Bus services - which account for about 70 per cent of Auckland bus trips and half of all public transport in the region - during last year's Rugby World Cup tournament.

It was reached after the former Auckland Regional Transport Authority withheld $1.1 million in subsidies from the bus company, which came under strong public criticism of its suspension of services during the lockout, forcing many commuters to walk to work.

The authority used some of the withheld money to pay $500 to each of the locked-out drivers, as part compensation for lost wages.

That was on top of a settlement that ultimately lifted their hourly pay by $2, in three stages to $18.75 by February this year.

According to the unions' stopwork meeting notice, the bus company is seeking a further three-year deal in return for an ultimate pay rise of 7.25 per cent, although the first instalment - of 2.3 per cent amounting to 43c - would not be paid until November.

The company has not commented on the negotiations other than to advise passengers to plan their travel carefully on Thursday, and to apologise to them in advance for any inconvenience.

Bus services run by Ritchies, Howick and Eastern, Birkenhead Transport, Urban Express and Airbus will not be affected.