Apart from a regular, Swiss income, I have some foreign income, which will be taxable in the UK. According to the DTA this income should be exempted from tax in Switzerland, but may be taken into account when determining tax rate (exemption with progression).

I am looking for a place to mention the exemption in the tax declaration, notably in VaudTax. I found an entry "Revenus imposable dans un autre Etat", but a) it didn't ask which country and I imagine different countries may have different rules b) it doesn't influence the calculation at the end. Any idea how to declare it?

I don't think in matters, but in my case the income come from restricted stock units, where part of the period between grant and vest was spent in the UK; according to a form on tax authority website, both parts (foreign and Swiss) of the gains should be declared.