PHP Form Intergration - Basket Format is Invalid

Okay this is bugging me and I need a little help or a second pair of eyes. I receive the following error message when testing and submitting my order confirmation form to sagepay for payment protocol 3.00:

Status: INVALID

Status Detail: 3021 : The Basket Format is invalid.

Here is the form content before encryption:

VendorTxCode=wilkies-PAYMENT-20150414141140-263293450
&Amount=245.72
&Currency=GBP
&Description= from J&D Wilkie Ltd
&CustomerName=Foo-Wing Li
&CustomerEMail=foo@jdwilkie.co.uk
&VendorEMail=foo@jdwilkie.co.uk
&SendEMail=1
&eMailMessage=Thank you so very much for your order.
&BillingSurname=Li
&BillingFirstnames=Foo-Wing
&BillingAddress1=Marywell Works
&BillingAddress2=Marywell Brae
&BillingCity=Kirriemuir
&BillingPostCode=DD8 4BJ
&BillingCountry=GB
&BillingPhone=+4401575572502
&ApplyAVSCV2=0
&Apply3DSecure=0
&AllowGiftAid=0
&BillingAgreement=1
&BillingState=
&customerEmail=foo@jdwilkie.co.uk
&DeliveryFirstnames=Foo-Wing
&DeliverySurname=Li
&DeliveryAddress1=Marywell Works
&DeliveryAddress2=Marywell Brae
&DeliveryCity=Kirriemuir
&DeliveryPostCode=DD8 4BJ
&DeliveryCountry=GB
&DeliveryPhone=+4401575572502
&BasketXML=<basket>
<item>
<description>Oil Absorbency 80x86cm</description>
<productSku></productSku>
<productCode></productCode>
<quantity>1</quantity>
<unitNetAmount>102.68</unitNetAmount>
<unitTaxAmount>20.54</unitTaxAmount>
<unitGrossAmount>123.22</unitGrossAmount>
<totalGrossAmount>123.22</totalGrossAmount>
</item>
<item>
<description>Removal Blankets - 60x108</description>
<productSku></productSku>
<productCode></productCode>
<quantity>1</quantity>
<unitNetAmount>102.08</unitNetAmount>
<unitTaxAmount>20.42</unitTaxAmount>
<unitGrossAmount>122.50</unitGrossAmount>
<totalGrossAmount>122.50</totalGrossAmount>
</item>
<deliveryNetAmount></deliveryNetAmount>
<deliveryTaxAmount></deliveryTaxAmount>
<deliveryGrossAmount></deliveryGrossAmount>
</basket>
&SuccessURL=http://ift.tt/1DeErir
&FailureURL=http://ift.tt/1DZbF91

Thanks