As Pope Benedict XVI starts his official visit to Spain, his views against gay marriage bring him into conflict with the secular Spanish Prime Minister Jose Luis Rodriguez Zapatero. A senior Vatican source revealed that Mr Zapatero, who brought in Spain’s gay marriage laws, is refusing to attend a Mass said by the Pope.

Cardinal Mario Pompedda told Italy’s Corriere della Sera newspaper that Zapatero’s decision was “an act of excessive secularism”.

And the Spanish right-leaning ABC newspaper said in an editorial that it was “a deliberate provocation.”

Not content with calling gay marriage an “anarchic freedom”, speaking to reporters on his plane from Rome, the Pope claimed, “there are certain things that Christian life says “no” to”.

He said that heterosexual family life “gives hope for the future”.

“We want to make people understand that according to human nature it is a man and a woman who are made for each other.

“We have families that love each other, who are happy, we want to stress this reality.” he said.

“Let’s shine a light on these positive things so we can try to make people understand why the Church cannot accept certain things but at the same time wants to respect people and help them.”

Spanish Law allows gay couples the same rights as straight couples to marry and to adopt children. Inheritance laws are also identical.

The 79-year-old Pope was greeted at the airport by King Juan Carlos and Queen Sofia of Spain, and by thousands of Catholics who waved banners and sang hymns and songs. He is meeting with families who lost loved ones in a train accident in Valencia last Monday that killed 42 people, and speaking at a conference for Catholic Families.

arrived in this coastal city to close an international meeting of Catholic families and comfort residents of Valencia still mourning a train accident that killed 42 people on Monday.