Boris Johnson said today that controversial adverts and leaflets being distributed in parts of the capital encouraging illegal immigrants to leave voluntarily could be worded "friendlier".
"Frankly the language could be friendlier...It's a fine point. But I think it's absolutely right to tell people to obey the law", the London Mayor said.
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Dozens of women gathered on Westminster Bridge to form a human chain in a show of solidarity with the victims of Wednesday's terror attack.
In a wide-ranging Peston on Sunday interview, he said Parliament security needs reviewing and the PM's counter-terror strategy is flawed.
The terror attack carried out by Khalid Masood at Westminster that left four people dead lasted less than two minutes say police.