In reality you will need A levels, I would say they have to be grade C or above as the days of A levels being the gold standard of education are long gone.
As WWW points out competition is fierce, therefore from a recruitment point of view you can have the cream of the crop.
If you don't have A levels, you could consider going to night school to get a few under your belt? I found the jump from GCSE to A level substantial, however with a bit of work you can easily achieve grade C or above.
WM