Readers' forum : A trust issue

A US citizen is deemed UK domiciled after living here for about 18 years. She was the beneficiary of a US trust of which she was the settlor. A few years ago with the sale of US property her wealth increased significantly. Her share of the sale proceeds ($US3m) were retained in the US and invested in a family portfolio worth about $US100m.

We are preparing the UK tax returns and there have been large capital gains in both the US trust and in a partnership which is in essence a pass-through vehicle. I am unable to ascertain the primary taxing rights of the US on these but have noted that tax payments for all of the capital gains have been made to the US. I am working off a US return as submitted to tax authorities there.

I have queried the primary taxing rights...