Filming an upcoming episode of Piers Morgan's Life Stories for ITV1, New Tricks star Waterman admitted that he was "very, very ashamed" after he "lashed out" and hit Lenska while they were married.
Welch has now claimed that her friend Lenska thought that she was perceived as "a liar" by the public when she accused Waterman of abusing her years ago, so is "glad" that the truth has finally come out.
Welch said on today's Loose Women: "I have spoken to her this morning and she knew that we were going to discuss it and all that she wants to say is that she is glad that he's eventually admitted it.
"Several years ago, when the marriage broke up and she first came out and made these allegations, she has since then been perceived as a liar by many quarters, some in the press and some from other people. So she is relieved he's eventually said it."
Waterman, however, has now been accused of trivialising domestic violence after saying that he hit Lenska but insisting that she was not a "beaten wife".
Sandra Horley, the boss of national domestic violence charity Refuge, told The Guardian: "I am appalled by Dennis Waterman's comments about his violence toward Rula Lenska, which trivialise the abuse he inflicted on her.
"It doesn't matter whether he hit her once, twice or a dozen times - no man is entitled to hit his wife and domestic violence is never acceptable. It is against the law."
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