As mayor of Newham, Sir Robin oversaw the regeneration of the east London borough as part of the 2012 Olympics.
However, his leadership style also faced criticism and he was ousted by Labour members after 23 years in power.
A London Labour spokersperson said Reform were “scraping the barrel” with the announcement.
“Neither men have been part of the Labour movement for some time. In Newham, Robin Wales was removed by local members following concerns about his record in office,” they said.
