Maina Kiai, the UN special rapporteur on the rights to freedom of peaceful assembly and of association, said he was "appalled" to hear about the blacklisting of union members in the UK construction industry.
Speaking on a trip to London, he said: "It is crucial that strong actions be taken against the making and using of such lists as a deterrence."
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The family of the police officer who was murdered in the Westminster attack have thanked those who were with him 'in his last moments'.
Thousands of fans gathered for a public memorial honoring famous mother and daughter who died just a day apart.
More sunshine this Sunday as British Summer Time begins.