Postage increase after buying item from international seller

[babybutch]

I recently bought an item from an International seller who posts 'Worldwide'. The price quoted for postage to Australia as per listing was EUR 15.00.

Paid for the item immediately via Paypal.

I have now received an email personally from the seller claiming that the shipping cost to my address is very high and it is going to cost EUR 100.

They claim they cannot send the item unless I pay this amount and have offered a refund back via Paypal.

I have sent them a message via the message centre asking them to honour the said price of postage as there was no mention of postage being revised or different as per their listing.

Awaiting their reply, but just wondering what I can do here.

Do they have to honour the listing?

Thanks,