Jeremy Bamber, who murdered five of his family members, and two other killers were told their whole-life tariffs amounted to a breach of human rights.
The European Court of Human Rights said whole-life sentences were "inhuman and degrading".
ITV News deputy political editor Chris Ship reports:
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The prince laid a floral wreath at one of a group of metal crosses near Wellington Arch in central London.
The group, which also owns Premier Inn, said on Wednesday that it will pursue a ‘demerger of Costa’.
The showers will become more frequent as the day goes on, giving some heavy downpours in places during the afternoon.