It' s a Daily Mail report about Islam, a topic on which they are well known to have a particularly unpleasant agenda. Therefore I would take very little of this report as reliable without seeing the evidence.
However, as usual they have buried the most relevant bit in paragraph 19 -
"The Muslim Council of Britain’s Ibrahim Mogra said: ‘UK law does not allow the marriage of underage girls and that’s all that matters to us here. In this country, it is illegal, it is forbidden and no imam should be allowed to conduct the marriage of an underage child.’"