A 19 year old man is still in a critical condition in hospital, after he was stabbed in New Cross Road in the early hours of Sunday morning.
He's thought to have been leaving a nearby nightclub.
More top news
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.
Two knives were found at the scene in Islington, North London, and the suspects fled on foot before being arrested.