Hi,
The guidance at DT4617, advises that 'Where a UK resident makes a lump sum withdrawal from an Registered Retirement Savings Plan (RRSP) or an Registered Retirement Income Funds (RRIF),
Canada imposes a 25 per cent withholding tax:
Double Taxation Relief Manual
No tax credit relief is allowable, which means that the full lumpsum is taxable in both Canada and the UK.
You can, however, claim a foreign tax credit relief of up to 100% of the foreign tax deducted, against your Uk tax liability.
Thank you.