Deputy Prime Minister Nick Clegg yesterday told Liberal Democrats to hold their nerve ahead of difficult local elections and a key voting referendum whose outcome could strain the 10-month-old coalition. “These are testing times for us as a party,” Clegg said as he closed a party conference in Sheffield. He was speaking a day after 3,000 demonstrators angry at government spending cuts had protested outside the central city hall where party members were protected by a steel fence and a phalanx of police officers. The party’s poll rating has more than halved to about 10 per cent since joining the Conservatives in coalition. “Yes, we’ve had to toughen up. But we will never lose our soul,” Clegg said.