In one message obtained by the Mail on Sunday, the Prime Minister thanked Mrs Brooks for letting him ride one of her horses, joking it was "fast, unpredictable and hard to control but fun".
In another the journalist, who faces trial in connection with the phone hacking scandal, praised Mr Cameron's speech to Tory conference, saying: "I cried twice."
The playful texts are apparently part of a cache of texts and emails handed to Lord Justice Leveson's media standards inquiry.
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Rain turning more patchy this afternoon but more persistent along the coast. Feeling cold in the brisk north-easterly wind.
Rain turning more patchy this afternoon but a little more persistent along the coast. Feeling cold in the brisk north-easterly wind.
The LGA wants chains with more than 20 outlets to display calorie counts as part of a plan to tackle childhood obesity.