John Armstrong: Breaking up is hard to do...just ask Peters

It was left to Winston Peters - never one to miss a chance to revel in his rivals' misfortune - to point out what was perfectly obvious to anyone watching Parliament yesterday.

"It is always sad when relationships fall apart," he declared without a skerrick of sympathy.

This may have been an understatement. The relationship between Act and National - supposed centre-right partners - is not just falling apart. The niggling is degenerating into outright hostility.

In what amounted to a declaration of Act's independence, Richard Prebble fired the first shot last week with his criticism of Don Brash. Yesterday, Act's leader, Rodney Hide, issued what amounted to a declaration of war.

National will take an extremely dim view of Act not once, but twice undermining its questioning of ministers on the two things where the Government is patently struggling - its handling of the NCEA and the troubled tertiary institute Te Wananga o Aotearoa.

Mr Hide's intervention during questions on the wananga was all the more extraordinary for helping Labour on the one issue where Act has made the running as part of its campaign to portray itself as the only party which is capable of holding the Government to account.

Not even the man once described as Act's "10th MP" is exempt from Mr Hide's efforts to make his party more relevant to voters by dragging it out of National's shadow.

Dr Brash had been trying to pin down the Prime Minister by getting her to confirm the Government had in 2003 exempted the wananga from new rules capping growth in tertiary institutions.

However, Mr Hide pointedly asked Helen Clark to confirm it had been a National Government which had "set the seeds" for the problematic explosion in student numbers at the wananga.

"Has she had any indication from the National Party that this is no longer their policy?" he added helpfully.

Given Helen Clark had come to the House with the strategy of trying to spread the blame in National's direction, she was only too happy to say no, before mentioning a few other things National had done to help the wananga get established, such as capital injections.

She then politely "acknowledged" Act for raising some issues which had prompted the Government to make further inquiries - issues which had not been raised by National MPs because the head of the wananga, Rongo Wetere, had been a "long-standing, active, high-profile" member of their party.

That was a killer blow and National never quite recovered during the remainder of question-time. Instead, it witnessed another Act MP, Deborah Coddington, ask Labour's Associate Education Minister David Benson-Pope if National had ditched its backing for the NCEA knowing it had not.

So far, National has avoided retaliation because that is exactly what Act wants to boost its profile outside Parliament.

Inside Parliament, however, Act could prove a real nuisance for National. There is grim irony in that.

Last year, Mr Peters was the one trying to derail National's attack on Labour by frequently siding with Labour in the House. Fearing NZ First will be seen as getting too close to Labour, he has put an election-year stop to that.

Now Act is doing what NZ First did - again at National's expense.