 Speaking in 1971, Sorensen suggested that the Government should 'positively encourage sterilisation, here and elsewhere, of those who are physically or mentally unfit' in order to stabilise the world's population.He had been offered the peerage to make a vacancy for the Foreign Secretary, Patrick Gordon Walker, who had been defeated in his Smethwick constituency.However, the by-election in January 1965 was won by the Conservative Ronald Buxton.