The Prime Minister, who has been under growing pressure since his father was named in the so-called Panama Papers, accepted he should have addressed that criticism when it first surfaced.
He faced jibes in the House of Commons today, with Labour MP Dennis Skinner suspended from the chamber this afternoon after making a comment about "dodgy Dave" - and repeating the remark when asked to withdraw it by John Bercow.
"We should defend the right of every British citizen to make money lawfully," Cameron said, adding there was "nothing wrong with people wanting to give money to their children".
He noted that offshore investment funds like his late father's Blairmore Holdings are "an entirely standard practice" - naming the BBC, the Guardian, the Mirror Group and Islington Council as organisations that also benefit from such practices.
Read more: Cameron's tax return in three simple charts
Cameron released a summary of his tax for last year but said he would not insist that other MPs must do likewise. He noted it could lead to a situation where other public figures and journalists would have to follow suit.
The Prime Minister insisted that no government has done more on the question of tax evasion and avoidance, noting that 129 jurisdictions have committed to implementing a new international standard for reporting tax information.
This summer Britain will become the first country in the G20 to set up a register of beneficial ownership, he added.
On top of this he unveiled three extra measures, including pledging to introduce a new law about facilitating tax evasion.
Crown dependencies - or so-called tax havens - would now be compelled to share information with British authorities.
"For the first time UK police and law enforcement will be able to see exactly who really owns and controls every company incorporated in these territories - Cayman Islands, British Virgin Islands, Bermuda, Isle of Man, Jersey, the lot," Cameron said.
"Under current legislation it is difficult to prosecute a company that assists with tax evasion, but we are going to change that, so will legislate this year for a new criminal offence to apply to corporations who fail to prevent their representatives from criminally facilitating tax evasion.
"We are providing initial funding of up to £10m for a cross-agency taskforce to swiftly analyse all information that has been made available from Panama and take rapid action," Cameron said.
As Cameron spoke to the Commons, chancellor George Osborne published his tax summary for 2014/15, while leader of the opposition Jeremy Corbyn has published his full tax return. True to form, it's an old-fashioned paper return.
|Panama papers latest: What you need to know|
More to follow....