In a letter, addressed to then European Council President Herman Van Rompuy, Cameron argued that offshore trusts should not be subjected to the same transparency requirements as companies.
“It is clearly important we recognize the important differences between companies and trusts,” he wrote.
“This means that the solution for addressing the potential misuse of companies — such as central public registries — may well not be appropriate generally.”
Cameron moved to distance himself from his late father’s Bahamas-based fund, saying that neither he, his wife or their children would benefit from any offshore trusts or funds in the future.
This was followed by another revelation that Cameron’s father was involved in a second company based in a tax haven.
A government spokesperson played down the significance of Mr Cameron’s lobbying efforts.
“At the time of the PM’s letter, the government was concerned that including trusts would distract from action against those areas of most concern, such as shell companies, and, in practice, these further changes weren’t achievable.
“In the subsequent negotiations, we were able to secure a sensible way forward which ensures that trusts which generate tax consequences have to report their ownership to HMRC [UK tax collecting department].”