The former X Factor judge and singer-turned-presenter Klass, who used to appear in the store chain's adverts, were dropped last year amid rumours that the company was alienating its older shoppers with young, attractive female celebrities in its TV commercials.
According to The Sun, the duo have now been reinstated and recently filmed some more adverts in South Africa with fellow ambassadors Twiggy, Lisa Snowdon, Noemie Lenoir and Jamie Redknapp.
The campaign, which will advertise M&S's summer collection, will reportedly feature Gary Barlow performing Beatles track 'Here Comes the Sun' to the other stars at a tea party.
Minogue wrote on her Twitter page earlier this week: "I did some filming in Cape Town, so UK tweet peeps should see me back on screen soon #Happy."
An inside source added: "Dannii might not be on The X Factor anymore but she is still considered a hot property and M&S were keen to have her back alongside Myleene. Both of them had a great time filming in South Africa and are thrilled to be back in the M&S fold."
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