Auckland Mayor Len Brown's office has rejected the suggestion his pledge to take public transport to work is off the rails.

Brown was joined by reporters on a train from Papatoetoe to Britomart on January 17 after releasing a statement saying he would "start taking the train to work on a regular basis as part of his commitment to public transport".

On his Twitter feed that morning, the mayor urged other Aucklanders to do the same.

"Great morning to be taking the train - I'm heading in from Papatoetoe to the city. Give the train a go, Auckland."

He pushed a similar message on his Facebook page: "Took the train in this morning, excellent trip. Beautiful weather, train nearly full, service running on schedule. Give it a go, Auckland."

Brown has travelled from his Totara Park home by car every day since.

When the Herald on Sunday photographed him being driven to work on Thursday, the first engagement on his official diary released the previous week was a 10am meeting in Orewa.

According to Auckland Transport's Maxx website Brown could have caught any number of trains to reach his office in time for a lift to the meeting in the mayoral limo.

On only two of the nine days since his high-profile pledge has Brown's official diary contained events that could have been tricky to get to by train - an interview at Radio New Zealand's Auckland studios at 7.20am on January 25 and the opening of the Norman Kirk Memorial Pool Complex in Otara at 9am on Tuesday.

Despite repeated requests, Brown wouldn't be interviewed.

Press secretary Melanya Burrows said: "He's not keen to talk to you on this, but would welcome you joining him on one of his trips in the coming weeks if you want to chat about things public transport."

Chief press secretary Glyn Jones said the mayor had many private meetings which weren't on his public schedule. On Thursday he had to be in Orewa early to brief his councillors.

Jones said Brown intended to take the train "as often as possible given his very full calendar, which has appointments all over Auckland, often starting early in the morning and going late".

She said he had two train commutes scheduled next week, and one for each of the following two weeks.

Campaign for better transport convener Cameron Pitches hoped Brown would follow through on his pledge.

"I'm prepared to give the mayor a chance but to encourage him to take the train as much as possible."

He added Brown was probably one of the most public transport-friendly mayors Auckland has had in a long time.

Auckland councillor and former North Shore mayor George Wood thought the mayor had "overcommitted himself".

"The mayor has a pretty busy schedule and he also has a driver and a car. I hope the mayor doesn't spend time on the train when he has other pressing commitments on behalf of the city."