EBay explained the move in a statement published on its web site:
"Beginning July 1 at 8 am BST, all fees displayed on eBay.co.uk will be gross fees, i.e. VAT will be included.
"VAT applies to eBay members who reside, have a permanent address, or are established in the European Union (EU). Under the EU regulations, we will apply the VAT rate applicable in a seller's country of residence, permanent address or establishment.
"Sellers who reside, have a permanent address or are established in a non-EU country, such as the United States, are not required to pay EU VAT on fees incurred by listing on eBay web sites within the EU."
EBay expects to catch any European sellers who try to avoid the VAT by using the US site eBay.com when they disclose their addresses - and at that point, the seller will be charged according to the rate in their home country, such as 25% in Sweden, 21% in Ireland or 17.5% in the UK.
Details of the new prices can be found at:
http://pages.ebay.co.uk/vat-landing/pricing/
The relevant VAT Directive of 2002 can be downloaded as a 4-page PDF