The European Union yesterday split over calls for a reference God or Christianity in the draft constitution, casting a cloud over fresh optimism that an overall deal will be struck next month

Foreign ministers from seven nations, including five of the EU's new countries, said a reference to the "Christian roots of Europe" is a national priority in negotiations on the constitution. But Spain, which had backed a mention of Christian heritage, has switched sides after the recent change of government, and yesterday backed France which guards its long-established secular traditions jealously. EU nations had been moving close to a compromise on the central issues blocking a deal, including the dispute over voting systems and the UK's demand to retain national vetoes in key areas. Jack Straw, the UK Foreign Secretary, said he was "incrementally satisfied" with talks on Britain's "red lines", amid signs that France and Germany were ready to strike a deal over most of them. The preamble to the draft constitution drawn up by the former french president, Valery Giscard d'Estaing, refers to Europe's "cultural, religious and humanist inheritance", without naming Christianity, thereby separating church and state. Along with Italy, Poland has been outspoken in its calls for a reference to Christian values; God is mentioned specifically in the Polish constitution. Those two countries were joined by Lithuania, Malta, Portugal, the Czech Republic and Slovakia in a letter to the Irish EU presidency demanding changes. France has little room for manoeuvre because its constitution has been a element in the ban on headscarves in schools there. Its Foreign Minister, Michel Barnier, rejected the letter and Belgium, Sweden and Denmark lined up behind the French. Mr Straw said he was "content" with M. Giscard's text adding: "If we were to go down the road of making specific references to one religious tradition, we have to bear in mind other specific religions and references to them as well." Spain's Foreign Minister, Miguel Angel Moratinos, also said M. Giscard's formulation is "perfect" for a secular government of a predominantly Catholic country such as Spain.