London: David Cameron had hoped to focus on campaigning to keep Britain in the EU before a referendum in June, but questions about his wealth, government spending and a steel crisis have blurred the prime minister's message.
After four days and four different statements over his late father's inclusion in the "Panama Papers", Cameron said on Thursday he once had a stake in his father's offshore trust and had profited from it, spurring calls for the leader to resign.
It is unlikely Cameron will follow Iceland's prime minister and leave office over the documents, which show how the world's rich and powerful stash their wealth, but the blow to his image could hurt his campaign to persuade Britons to stay in the European Union.
On Thursday, Cameron used a television interview to admit he had a holding in his late father's Panamanian trust, Blairmore, but had sold it in 2010 before becoming prime minister.
"Of course I did own stocks and shares in the past - quite naturally because my father was a stockbroker.
I sold them all in 2010, because if I was going to become prime minister I didn't want anyone to say you have other agendas, vested interests," he told ITV television.
"We owned 5,000 units in Blairmore Investment Trust, which we sold in January 2010.
That was worth something like 30,000 pounds." ($42,000)
He underlined that he had paid tax on the dividends and on the profits, and said his father had left him 300,000 pounds on his death.
He also suggested he had not immediately detailed his affairs because he had struggled with the critical coverage of his father, "a man I love and admire and miss every day".
Cameron said the unit trust was not set up to avoid tax but to invest in dollar-denominated shares and he also promised to publish his tax returns.
There is no indication that he or his father had done anything illegal, but by casting a spotlight on the Eton-educated Cameron's wealth, the admission has fuelled a public perception that his Conservative Party rules to protect the rich while punishing the poorest with its austerity push.
Opposition politicians said his initial reluctance to describe his financial connections with his late father after the Panama Papers were leaked on Sunday begged more questions of the leader, who has championed policies to reduce tax avoidance.
"Far from being the end of the matter, the questions keep coming," said Tom Watson, deputy leader of the opposition Labour Party.
"Did the prime minister know that this fund was linked to tax avoidance? If so, when, and if not, why not? Given that he claimed that "sunlight is the best disinfectant", why has it taken six years for this to come to light?"
Calls for Cameron to resign trended on Twitter, with one user saying that if "Iceland can do it, I'm bloody sure the UK can too".Others accused him of hypocrisy for having used an offshore unit while calling for an end to tax avoidance.
Prime Minister Sigmundur David Gunnlaugsson quit his position on Tuesday after the leaked files showed his wife owned an offshore firm with big claims on Iceland's collapsed banks.
Government ministers played down any chance of Cameron's removal from power, but the revelations will only fuel growing discontent in his ruling Conservative Party over the leading role he is playing in the campaign to keep Britain in the EU.
The June 23 referendum on Britain's EU membership has split the party, with many accusing the prime minister of breaking his promise not to undermine the "Out" campaign by spending 9 million pounds of government money on pamphlets they say are biased in favour of remaining in.
Accusations that his government has allowed Britain's steel industry to all but collapse, leaving thousands out of work, have further eroded his public appeal as the leader of the "In" campaign.
At a campaign outing on Thursday to rally youngsters to his cause, Cameron was ambushed by students, fielding questions touching on his "personal experience of tax avoidance", his refusal to bail out the steel industry and whether he felt government pamphlets gave the "In" campaign an unfair advantage.
Asked whether Cameron was now tarnished, Nick Boles, the skills minister, said that perhaps with hindsight, Cameron should have detailed his financial affairs earlier.
"I don't think it has (done damage)," he told BBC radio."I think people are fair-minded."