A war has begun…

After Gwen Stefani and Gavin Rossdale officially separated, their divorce proceedings have reportedly taken a turn for the worst, as Gavin is demanding spousal support and the ex-couple’s marital home.

A source told Radar Online, “Gwen can’t believe that Gavin is asking for their Beverly Hills mansion as part of the settlement,” adding, “She thought the only issue of the mediation would be finances since they have already agreed to joint custody of their three children.”

The 49-year-old musician is allegedly asking for $50 million as well as monthly child support and spousal support.

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With no prenup in place, the 46-year-old No Doubt singer could be paying “upwards of at least $50k” every month.

The insider revealed, “It absolutely disgusts Gwen that he is asking for so much money after she feels he betrayed her.”

In Touch previously reported details of the British rocker’s rumored infidelity. The pair filed for divorce back in August after 13 years of marriage.