World celebrates election of London's first Muslim mayor

Sadiq Khan was sworn in as London mayor on Saturday after a bitter and grueling election campaign, become the first Muslim leader of a major Western capital.

The 45-year-old Labour lawmaker - the son of a Pakistani bus driver who grew up in social housing in the city - won 57 percent of the vote in Thursday's mayoral election.

He secured 1.3 million votes and made history as the city's first Muslim mayor.

Hillary Clinton - the likely Democratic nominee for the US presidency - led international congratulations through her Twitter account.

Khan's wide margin of victory was seen as a repudiation of the Islamophobic campaign waged by his main rival, the Conservative party candidate Zac Goldsmith. 

His own sister, Jemima [formerly married to Pakistani politician and cricketer Imran Khan], expressed regrets about it after her brother's 14-point defeat was confirmed.

In his victory speech in the early hours of Saturday morning, Khan referenced the negative campaign against him by saying London had chosen "unity over division".

Conservative Prime Minister David Cameron had led the attacks against Khan for sharing platforms with radical Muslim preachers at public events.

On the other hand, Khan's election as the mayor of London has been hailed by many as a "victory for Islam", while others considered it to mark the success of a secular and tolerant democracy.

Some social media users used Khan's victory to show how it exposed double standards and paradox in Arab and Muslim societies.

Translation: Sadiq Khan is the first [Muslim] mayor of London. This is an accomplishment for Western democracies and a lesson for Arab policies, as we no longer accept the others.

Translation: Sadiq Khan has been elected as the mayor of London, and we are still fighting about Sunnis and Shias and referring to each other's origins and tribes! Wake up, Arabs!

Translation: The most disgusting thing about those who are happy with Sadiq Khan as the mayor of London are the same people who would move out if they had a Christian neighbour!