APART from politics and sex, there is nothing quite as combustible as politics and money.

This week must have seemed particularly long for our noble leader David Cameron as he battled not only on the EU front and the outcry over that £9.3 million taxpayer-funded leaflet but on the tax haven front too.

Panamagate, as it will undoubtedly become known, has proved that if you take the high moral ground, make sure you’re not standing on a volcano.

One sensed something was up when on Monday, the Prime Minister’s aide took a particularly aggressive line on the tax haven story, which had broken over the weekend.

At first, she sniffily dismissed it as old hat, suggesting people should turn to Google to refresh their memories, and then, when pressed, insisted it was a “private matter”. Her indignation at the impertinence of Her Majesty’s Press asking such questions gave the game away; ‘twas ever thus.

And so the days unfolded with headline following headline as Mr Cameron ducked and dived, issuing statement after statement that suggested there was nothing to see here; please, people, move on.

But after his fifth clarification, the PM was forced to admit that he had indeed benefited from money stashed in the treasure island of the Panamanian tax haven. Yet, he made quite clear that the trust was not about avoiding tax and that he had, in fact, paid all tax that was due.

So that’s that then? Not quite.

There are still questions about whether or not the PM held any other units or shares, which might have benefited from being in a tax haven. Then there is the £300,000 inheritance he received from his late Scottish stockbroker father. Was any of that money derived from a tax haven vehicle?

Process aside, there is also the little matter of public trust.

The events of this week and the prime ministerial wriggling will for out and out critics of Mr Cameron only confirm their worst feelings about the Tory toff. For other more even-minded souls, they will have raised suspicions about his integrity and trustworthiness; quite important features in a prime minister.

Of course, Panamagate could not have happened at a worse time as the Conservative leader seeks to convince voters of the merits of Britain staying in the EU and as his party attempts to win votes in elections in Scotland, England and Wales. A penny for Ruth Davidson’s thoughts as she battles to detoxify the Tory brand north of the border.

Understandably, Labour and the SNP are making political hay at the PM’s expense. On Monday, Mr Cameron will have his helmet on as his political opponents lob barb after barb at him but, remember, the PM tends to be at his best when he has his back to the wall and Jeremy Corbyn’s skill at missing open parliamentary goals is becoming legendary.

Next month, a battered premier will seek to regain the high moral ground on tax evasion and avoidance when he hosts an international anti-corruption summit in London. He will just have to make sure the volcano beneath his feet is not about to erupt again.