In Spain, hundreds of thousands of supporters of a unified nation filled Barcelona's streets yesterday in one of the biggest shows of force as regional political leaders push for Catalan independence.<br/><br/> Political parties opposing a split by Catalonia from Spain had a small lead in an opinion poll published yesterday, the first since Madrid called a regional election to try to resolve the country's worst political crisis in four decades.<br/>'<br/>Spain's central government called an election for December 21 after sacking Catalonia's president Carles Puigdemont, dissolving its parliament and dismissing its government. <br/>'<br/>At the rally, former European Parliament president Josep Borrell called for unionist voters to turn out in December to ensure independence supporters lose their stranglehold on the regional parliament.<br/>'<br/>European countries, the United States and Mexico have also rejected the Catalan declaration of independence and expressed support for Spain's unity.