Opposition leader Simon Bridges described the government's Budget decisions as "flabby spending", influenced by promises to New Zealand First.
The National Party leader yesterday said Budget 2018 was a "very surprising Budget".
"People would have expected, given the rhetoric, that this government would be putting a lot more into health and education.
"They just haven't."
Health was given $4 billion and education was allocated $1.6b in operating funds, $590m for early childhood and $284 to Learning Support.
Mr Bridges said when in opposition, the government made promises in health and education, and he could understand why some people in those sectors may be disappointed.
"They're awash with cash, they've just got billions and billion of dollars from a strong economy, higher revenues that they thought, good books anyway, more tax, more borrowing.
"Then you say, what the hell is going on here?"
He said one of the reasons was "Winston".
Mr Bridges said the $1b for foreign affairs and $3b over three years for the Provincial Growth Fund was "flabby spending".
He said there were arguments why the almost $1b into foreign affairs was beneficial, however, "when you're not doing the cheaper GP visits, when you're not doing the full police numbers you promised, when you're not funding mental health that you promised, it's kind of a strange priority".
"There's been money there, but they've put many billions into other things. Diplomats, free fees, winter energy payment."
"It's big, it's flabby spending and it's very different from what we would have done, where it would have been targeted."
Mr Bridges said he did not see anything in Budget 2018 "that adds the cream".
He said it could be considered a wasted opportunity.
"Perhaps that's the label of this Budget, 'The Budget of Wasted Opportunities'."