You will probably need a 'Let to Buy' mortgage. However, this mortgage will be assessed on your salary and not on the potential rental income of the property (as a Buy to Let mortgage would be).
A good independent mortgage broker will be able to talk you through the options.
It really depends on your situation and rational/motivation for doing this.
I would say if you do not need to do it why take the risk?
With property prices falling and the credit crunch just getting started you're just increasing your debt whilst at the same time doubling your equity losses, whats to recomend it, if you're a discretionary second property buyer?