The director for the Coalition for Marriage has handed a petition to Downing Street against plans to change laws to allow gay marriage.
Colin Hart told press outside No 10 that "the government should listen to the people" and to keep existing marriage legislation.
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Arkansas has become the first US state in 17 years to carry out back-to-back executions after putting two inmates to death.
Up to three million children risk going hungry over the school holidays, with increasing numbers of families relying on food banks, MPs say.
Tuesday will be a cold and windy day across the British Isles with a mix of sunshine and showers.