How about this for an idea? Benefits only paid to UK citizens?
Citizenship only granted after 12 months crime free occupancy, and an oath of alliegance sworn to their benefactor - THE COUNTRY THAT FEED THEM
Why 12 months?
The Roman empire had the right idea, outsiders could only gain Roman citizenship after 25 years military service to the empire, now that could be a better starting point.
And on the subject of military service I believe the government should announce the idea of forming a muslim regiment of the British army (Just like the Germans did in the second world war but without the ss badges!). Then the muslim community who say that the extremists who don't represent them can join up to help stop the more radical elements and also be more sensisitve when on attice service in the middle east.
It wouldn't cost anything either --because it would just be an announcement I don't really think there would be more than a handful of volenteers.