A key adviser has said that US Republican presidential candidate Mitt Romney would back Israeli military strike against Iran nuclear programme, according to the Associated Press.
The visit is the latest part of a three-nation trip that includes Britain and Poland.
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It will be increasingly humid and thundery with highs of 30C or more today.
Holidaymakers in Tunisia are determined not to be beaten. But, as Neil Connery writes, it won't be easy to escape the shock of the massacre.
Drink lots of water, stay out of the sun during the middle of the day, and take particular care of vulnerable people.