There have been cases of British citizens being blackmailed, bullied and forced into marriage to obtain British Citizenship. Stronger laws should be placed to stop sham marriages.
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British citizenship should only be granted to foreign nationals after 8 years of being together. A temporary British passport can be granted however, the temporary British passport could be terminated if separation takes place before 8 years. The foreign national will be expected to return home if a divorce takes place before the 8 years.