"We are redirecting money that had been promised by the previous Government in across-the-board tax cuts to more targeted spending - on health, education, and for families with children," he said.
"We can make these investments while not having to increase taxes. We do this by having different priorities to the previous Government - reversing the proposed tax cuts and giving ourselves two extra years to meet the Government's debt-reduction target."
Robertson said the Government had a "comprehensive reform agenda" for Auckland including a Housing Commission, which he described as "an urban development authority to cut through the red tape and lead large urban development projects".
He repeated that the Government will scale back spending on the East-West transport link and said infrastructure bonds would be used to fund major projects.
"We are committed to implementing a $15b, 10-year programme to build this rapid transit system - including light rail from the CBD to the airport and out to West Auckland," he said. "We are also investigating third-tracking the main trunk rail line and electrifying the rail line to Pukekohe."
Robertson said the Government would involve Maori in its infrastructure goals and would look to work with the private sector including public-private-partnerships (PPPs).
"We don't believe PPPs have a place in schools and hospitals, but there is a potential for partnerships which can be used to drive productive and sustainable growth where they are appropriate," he said.
Unlike previous years, there would not be the usual slew of pre-emptive announcements before next year's Budget.
"The plan is already out there. The first steps towards Budget 2018 will come this Thursday," Robertson said.
National Party leader Bill English said Robertson didn't have any good reasons for ditching PPPs for schools and hospitals.
"The PPP for schools have worked very well. If he actually visited the schools that have been built that way, they'll find that the boards and the teachers can focus entirely on the achievement of the kids and don't have to spend a whole lot of time on the property. They are well-built schools, on time and under budget.
"PPP have worked well in our schools, well on the roads, they were getting underway in housing ... and are a good way to manage the taxpayers' dollar better.
"Labour are canning them - not because the public is opposed to them or because they don't work, but because Labour didn't like them. And that's not a good enough reason."
English expected the HYEFU to show debt to track from the current level of about $58b to about $70b in the next few years.
"After the 100-day plan, there won't be much left for anything else."