Mrs Brooks told the Leveson Inquiry earlier this year that Mr Cameron signed some of his missives to her 'LOL' - mistakenly thinking it meant 'Lots of Love' rather than 'Laugh Out Loud'.
Both of the messages disclosed by the MoS were sent in October 2009, shortly after Mrs Brooks left her job as editor of The Sun and became chief executive of News International, which owns the paper.
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Showers this evening then dry overnight.
Showers this evening then becoming dry but cloudy overnight.
The Prime Minister praised the armed forces as she joined celebrations in Liverpool.