"No wonder the Prime Minister is beginning to crack under the pressure. Not only does everything her Government touches turn to custard but she has Bill English subtly undermining her at almost every opportunity," Labour finance spokesperson Michael Cullen said today.

"He was at it again yesterday, telling the Dominion he was "not hanging too much" on the March quarter gross domestic product result, due out on Friday, in clarifying his desperately vague thinking on the potential for another tax cut.

"This is in stark - and, no doubt, deliberate - contrast to the hapless Mrs Shipley's comment on National Radio that morning that Friday's growth figure would be "a very important indicator" in determining the National Party's stance on further tax cuts.

"It's not the first time the two have disagreed on tax. On March 12, Mrs Shipley told the Dominion: "You can't keep reducing taxes indefinitely without having clear expectations of what government services will be available."

"And two weeks later, Mr English told the Press: "It's not an either/or choice of either tax reductions or social services. If the country does well, we can have both."

"He also lined up on the opposite side of the debate to her on whether the drinking age should be reduced to 18. She thinks it should. He thinks she's wrong and was at pains to spell out all the reasons why.

"No wonder commentators are beginning to speculate that Mr English wants a spell in Opposition because he knows that is his fastest route to the leadership," Dr Cullen said.

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