Were you in or around Streatham Common Southside during the morning of Monday 9 September or in the time leading up to or after the attack and did you see a man fitting this description?
He was wearing gloves and a thick puffa jacket which may have made him stand out.
It is possible that he may have been seen in this area in the days before the attack or maybe even approached other women. If you saw him or he approached you please do get in contact with us.
Anyone with information should contact the investigation team on 020 8649 2419 or alternatively contact Crimestoppers anonymously on 0800 555 111.
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.