The Prime Minister said today that it is in the national interest to be part of the European Union but that this doesn't mean it cannot opt out of certain measures.
Speaking at the European Summit in Brussels, he said there was a "false choice" between going along with all of the reforms of the Union and leaving it.
Asked whether there is a growing impression that Britain is not interested in the EU, David Cameron said he has a reputation for plain speaking but is not anti-EU.
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Rain in the north tonight, cloudy and humid in the south
In an exclusive interview with ITV News, 100 metre world champion Justin Gatlin also said that booing at the World Championships "did hurt".
The 26-year-old had just given birth to her third child and was being transferred to a different floor when the tragedy happened.