London (CNN) -- British Foreign Secretary William Hague met a range of Syrian opposition figures Monday, saying London was "seeking to step up the international pressure on the Assad regime, a regime that has long since lost its legitimacy in the eyes of the wider world." Syrian President Bashar al-Assad needed to know that "the rest of the world is talking to the Syrian opposition and we are looking for a different future for Syria," Britain's top diplomat said. "I think the Assad regime will find that more and more governments around the world are willing to work with the opposition," Hague said.
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NEW: More and more countries will meet the opposition, William Hague says
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Britain is "seeking to step up pressure" on Syria, the foreign secretary says
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Hague urges opposition groups to unify
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The United Nations says more than 3,500 people have died in the Syrian crackdown
@placeholder's government has said it is fighting armed terrorists, maintaining the death toll is much lower than international observers and opposition groups say.