self assessment tax return / foreign pages

I am a Belgian, UK tax resident and receive a civil servant government pension from the Belgian authorities : do I declare and can I be taxed (in UK) on this Belgian pension ? However info europe.eu Pensioners moving to another EU country : “Exemptions : Government pensions only taxed in the country where the employee was employed “

Hi,
You can see guidance here:
Tax on foreign income
Thank you.