http://www.caa.co.uk/docs/33/LASORS_06_WEB.pdf
That is a near 12mb file. It is the document that outlines all the flight crew licensing rules for the UK CAA. You need to read it and then call them.
One area I would particularly check is that you can get the necessary security check completed for an airside pass. A background with the Pakistan Military might be seen as a bit special.
Good luck,
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