Harold Wilson confessed to an affair during his final year in Downing Street, one of his closest surviving aides has revealed for the first time. The former Labour prime minister had a secret affair with Janet Hewlett-Davies, his former deputy press secretary who was 22 years his junior, towards the end of his time in No 10. Joe Haines, Wilson’s former press secretary, revealed the affair in an interview with the Times on Thursday. Haines said he was told of the “love match” between Wilson and Hewlett-Davies, who were both married at the time, before the prime minister’s resignation in 1976. “More than anyone could know, she was of significance to the last Wilson administration: she was Harold Wilson’s mistress,” Haines told the Times. “She died nursing a secret which never leaked from Downing Street, the most notorious leaky building in Britain. “It was certainly a love match on her side, and the joy which Wilson exhibited to me suggested that it was for him too.” Another of Wilson’s closest advisers, Bernard Donoughue, who was also made aware of the affair, told the BBC Radio 4 Today programme that revealing it now was important for the “historical record”. Lord Donoughue said he and Haines had decided to make the half-century-old secret public after Hewlett-Davies’ death in October. “We kept it secret because we thought it would be used damagingly against him at that time,” Donoughue said. “There’s no reason for that now, and we waited until they had both died, Wilson some time ago and Janet just a few months ago, and so I felt as a sometime historian this was important to go in the historical record of Harold Wilson.” Wilson, who was prime minister first between 1964 and 1970 and then again between 1974 and 1976, died in 1995 at the age of 79. Wilson’s wife of 55 years, Mary, died in 2018, aged 102. During his time in office, there were persistent rumours that he was having an affair with his political secretary Marcia Williams, with whom he had a tumultuous relationship. He ennobled Williams as Lady Falkender in 1974. Donoughue said Wilson had cryptically confessed the affair to him during a walk around No 10 towards the end of his premiership. “He, in a very Wilsonian way, because he wasn’t a very direct person, he said he was very pleased I was a friend of Janet,” Donoughue said. “So I, knowing him, know that he would not have raised that unless he had got some interest or concern, so I knew that he was asking me: did I know about him and Janet? “And I replied by saying I thought Janet was a lovely and terrific person and I then added, in a Wilsonian way, which I had learned from him ‘and I’m very pleased your relationship is so close and so good’.” “And that way I let him know that I knew, and then he said that she was a lovely person and he had never been happier.” Donoughue said the affair had provided “a little sunshine at sunset” for the prime minister, who was becoming increasingly paranoid about the security services and dealing with a very narrow majority, economic difficulties and, it has been suggested, the early stages of dementia. Haines told the Times that Wilson’s affair “increased his morale in the last two years or so before he retired”. He said he found out about the affair “by pure chance” when he saw Hewlett-Davies climb the staircase to Wilson’s room in Downing Street one evening in 1974, long after the press office had finished work. “I said nothing to her that night, but next morning asked what she was doing there,” he said. “She told me she was waiting for Wilson, and then told me why. I, too, kept the story secret in all that I have written about my time at Downing Street.”