By Nick Assinder BBC News Online political correspondent

Like a couple of pit bull terriers, the two men wasted little time on niceties but lurched at each other, snarling, snapping at the neck.

It was one of the most venomous question time exchanges many can remember for years.

By choosing to go on the issue of beleaguered children's minister, Margaret Hodge, Mr Howard zeroed in on the core Tory attack on the government.

That is, that it dissembles, smears and then uses its full might to bully people who dare cross it.

Calm down

And the language was as personal, even vicious, as is possible within the rule of Parliamentary etiquette.

It hyped up the ever-excitable backbenchers to such an extent that the Speaker had to step in time and again to calm things down. To no noticeable effect.

Mr Howard accused the prime minister of having lost all sense of shame and of being more concerned about protecting vulnerable ministers than vulnerable children.

And he reeled off a series of previous alleged victims of government bullying.

It was a highly effective assault and it came close to driving the prime minister over the edge.

His fury was palpable - it was at this point he literally, if inadvertently, spat his response back at the opposition leader.

Sneering answer

He was seething that, just as he thought the Hodge affair was behind him, Mr Howard was determined to keep it going. This is one scalp the Tories still believe is winnable.

And he was probably also angry that, thanks to some neat footwork by the opposition leader, he was not able to wield his dossier of past "Tory shame".

Indeed, Mr Howard completely wrong footed him by starting with a straight, inclusive question welcoming President Bush to the UK.

But the prime minister had obviously decided after last week's mauling that he was going in hard from the off.

So he rather miscalculated with a somewhat sneering answer claiming this, presumably, was Mr Howard attempting to be statesmanlike.

No, it was Mr Howard keeping you guessing Tony.

It was also Mr Howard seeking a way of pushing the prime minister to the edge of his self control, while maintaining his own.

And, it has to be said, he succeeded so there will be much more of this.

How on earth the clashes can get any more aggressive without the need for medical assistance, however, remains to be seen.