Kate Middleton asks royal jewellers to adjust her engagement ring from Prince William

Princess-to-be Kate Middleton's finger is too slim

Kate Middleton will marry Prince William on 29 April

Kate Middleton has reportedly had to adjust her engagement ring from Prince William because it keeps slipping off her finger.

The diamond and sapphire sparkler, which belonged to Wills' late mum Princess Diana, is said to have been fitted with 2 platinum beads by royal jewellers G Collins & Sons.

'Rings with a really heavy rock - particularly one such as this - have a habit of twisting round on the finger,' jewellery expert Robin Haydock tells the Daily Mail.

'Attaching small beads in strategic places on the inside of the band helps to stabilise the ring without having to adjust the band itself.'

Skinny-fingered Kate, 29, looked slimmer than ever as she made her final public engagement with Prince William, 28, earlier this week.

'Kate's shed weight rushing around planning the wedding,' a source recently revealed to Now.

'But she's worried that she'll lose her curves completely, so she's introducing a lot more carbs into her diet.'�

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