The 42-year-old supermodel has called time on her romance with Nikolai, 29, after one particularly "heated argument" which was the final straw in a long string of rows for the couple, reported Female First.
"Kate and Nikolai have been arguing a lot in the last few months but they had one row recently which was the final straw. It sounds like it was a really heated argument and Kate has said she is done with him after that," a source said.
On top of the arguments with Moss, Nikolai is also reported to have been at loggerheads with Kate's 14-year-old daughter Lila, who "didn't approve" of their relationship.
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