Politicians from the main parties have hailed the change in the law.
David Cameron said the move sent a message that people were now equal "whether gay or straight", but some religious groups remain opposed. Scotland passed a similar law in February; the first same-sex marriages are expected there in October.
Northern Ireland has no plans to follow suit. In an article for the Pink News websitethe prime minister wrote: "This weekend is an important moment for our country. He congratulated his party for being part of the reform, saying: "If our change to the law means a single young man or young woman who wants to come out, but who is scared of what the world will say, now feels safer, stronger, taller - well, for me, getting into coalition government will have been worth it just for that.
However, he warned that the "battle norwlch true equality" was not yet won. Human rights campaigner Peter Tatchell acted as chief witness at a packed ceremony at Islington Town Hall in London just after midnight as Peter McGraith and David Cabreza were wed after 17 years together. Mr Tatchell said the couple and all the others getting married had "made history" and "made Britain a more tolerant, equal place".
With a crowd of photographers, journalists and well-wishers waiting, the couple took the opportunity to highlight the international struggle for gay rights. Mr McGraith said: "Very few countries afford their gay and lesbian citizens equal marriage rights norwiich we believe that this change in law will bring hope and strength to gay men and lesbians in Nigeria, Uganda, Russia, India and elsewhere, Light porn mather. lack basic equality and are being criminalised for their sexual orientation.
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Aarron Adem Erbas, who married Louis Monaco, also at Islington Town Hall, said: "We're going to celebrate the rest of the day and it means so much to us that we can have our friends and norwichh ones here. It's absolutely brilliant.
bit The couple, who entered into a civil partnership seven years ago, exchanged vows on stage at the Royal Festival Hall in London at a special event to celebrate the introduction of gay marriage in the UK. Toksvig, who presents the BBC Radio 4 News Quiz, said it was "an astonishing moment in history", adding: "There was many a time I thought this day would never come.
But some religious groups remain opposed to gay marriage. Andrea Williams, chief executive of Christian Concern, said: "We can't just redefine an institution - redefine something that always has been - because we say it's something that we want.
This is not about rights, it's about seeking cultural dominance and seeking to redefine marriage for all of us. The CofE has urged clergy to support members of the congregation who are in same-sex marriages, but has ruled that priests themselves must not enter into one.
The Roman Catholic Church opposes the change in the law. Some gay vicars, though, have said they are prepared to defy their bishops by insisting they have a right to marry. Mr Cain, who plans to marry his partner in the summer, said he would do so whether the Church approved or not.
I could lose my job, absolutely. Lose my job, my home and my place.