Carphone Warehouse and Phones4u won't be stocking Windows Phone 7 handsets on Microsoft's big launch day, 21 October, Pocket-lint has learnt.

The news will come as a massive blow to readers looking to snap up the new Windows Phone 7 handsets at either of the two massive retailers. They'll have to go direct to an operator instead.

"Windows Phone 7 handsets won’t be in store tomorrow. We will be stocking them soon", a Carphone Warehouse spokesperson told Pocket-lint.

It will be selling the Samsung Omnia 7, available on Orange, Three and T-Mobile and the HTC HD7 available on O2, just not on day 1.

Meanwhile, Phones4u has told Pocket-lint that it won't be getting stock of the Orange HTC 7 Mozart until the 29 October due to stock storages.

"Its now the 29th due to HTC delays", an online sales rep told us via the company's website live chat service.

While the Orange press office has confirmed to Pocket-lint that it will have stock in its dedicated stores, and online for the big 21 October launch day; Phones4u isn't so lucky.

According to the retailer, which opted to only stock the Orange handset rather than the whole Windows Phone 7 range from launch; the Mozart won't be coming to Phones4u stores until 29 October - a full 8 days after launch, suggesting stock will be very tight.

It's a far cry from the words of Windows Phone 7's big cheese Oded Ran, who told us at the 11 October launch that there would be no delays and that all was set for the 21 October launch date. 

The news comes as rumours started surfacing earlier in the week that HTC was having manufacturing problems due to a number of software glitches, something that it denied.

While the maker of three of the handsets has been able to meet their deadline, it seems that both HTC and Samsung have not been able to bring enough devices into the UK to meet the requests from all parties.

The US launch is scheduled for the 8 November.

Windows Phone 7: Where to get it on UK launch day