Tax by cash gift

I will receive HKD4,000,000 (approximate 400,000 pounds) from my mother in law for the purpose of purchasing a house in UK. She will deposit the money by cheque into my personal bank account in Hong Kong. I will exchange the money into pounds sterling and remit the money into my UK bank account. Do I need to provide supporting documents as it is a gift? Do I need to declare to HMRC on the remittance amount? Any documents I need to fill in ? Thanks for your advice in advanced.

Hi,
We can confirm that there are no Income Tax implications on the receipt of a cash gift unless the cash gift generates interest or dividends.
These would then potentially be subject to tax.
Thank you.