Major UK retailers have begun warning customers they may not get their hands on Nintendo's Wii on the launch day - even if they pre-ordered the console. Sellers say the vendor has shipped too few units to meet demand.

Reg Hardware today received a number of emails from readers who were last night contacted by Woolworths to tell them their pre-ordered Wiis might not arrive until Christmas.

"Nintendo have only shipped part of the promised stock for Nintendo Wii to all retailers within the UK," the retailer told pre-order customers. "Due to this, we have only received part of our allocation. We are led to believe by Nintendo that we will receive all stock in time for pre-Christmas delivery. Please accept our apologies for this delay."

Woolworths' email suggests the problem is not restricted to it alone. Indeed, we also heard today from readers who claimed Amazon.co.uk had issued a similar warnings to its pre-order customers. Again, it appears the online retailer may not get enough stock to supply consoles tomorrow, though it appears to be promising to get product out to buyers before Christmas.

Woolworths' comments mirror comments made today by DSG Group, owner of Currys, PC World and the dixons.co.uk website, that while it expects to be able to meet pre-orders for the Wii, it may not be able to supply consoles to anyone else.

"We're expecting four deliveries between now and Christmas and we expect them all to go to pre-orders," the company told website GamesIndustry.biz.

"If customers haven't already pre-ordered then they've probably missed the boat."

Nintendo is due to launch the Wii here tonight at midnight with a big, minor-celebrity bash at the HMV Oxford Street store here in London. ®

Read Reg Hardware's full review of the Wii here

Read Reg Hardware's complete Wii launch coverage here