A British tabloid is reporting dubious -- but delightful -- details of an alleged carb-fueled spat between Gwyneth Paltrow and Kate Moss last week.

The leggy blonds were at a Mexico resort to celebrate Sir Phillip Green's 60th birthday. According to a source speaking to the Sun, the trouble started during Gwyneth's pre-party workout.

Gwyneth had gone for a jog on the beach before the big birthday bash. Kate was out for a walk, eating crisps, when Gwyneth ran past, the source reportedly said.

Kate said, 'Oi, what you out jogging for?' Gwyneth fired back, 'So I don't look like you when I get old'. Kate was speechless for a second then spat back and threw some crisps at her. She said, 'Why don't you eat some f***ng carbs!'

The best part of the alleged story: Paltrow is older than Moss -- by one year.

Apparently, news of the rumored sparring session quickly made its way around the celebrity-packed resort.

The spat was the talk of the dinner. Everyone was having a giggle about it, the source said. Kate is seen as queen of the cool crowd but not everyone falls into line.

At press time, the Sun report has not yet been independently corroborated from another outlet, and Paltrow's publicist denied the report in a statement to the Daily Mail.

There was no such fight, the spokesperson said. This is a fabrication.

Paltrow herself has not made any comments about the rumored spat via Twitter -- she's still working on clearing what she claims are inaccurate reports that she employed a ghostwriter for her cookbook.