Sebastian Coe has been elected as the new president of the International Association of Athletics Federations.

The former London 2012 chairman saw off the challenge of Ukrainian Sergey Bubka in a vote at the IAAF Congress in Beijing on Wednesday to net the top job in world athletics.

The two-time Olympic 1500 metres champion secured the support of the majority of the 207 IAAF member federations who voted, winning by 115 votes to 92.

Lord Coe succeeds Lamine Diack, the 82-year-old from Senegal, who has been president since 1999, and becomes only the sixth president in the IAAF's 103-year history.

Speaking to the Congress after his victory was announced, he said: "I have to say that being given the opportunity to work with all of you to shape the future of our sport is probably the second biggest and most momentous occasion in my life (after the birth of his children)."

The 58-year-old's elevation from vice-president, a post he has held since 2007, comes at a crucial time for the organisation, with allegations of mass doping and cover-ups threatening to ruin the already fragile reputation of the sport.

The Briton, who had been the strong favourite to win, has highlighted the need to overhaul the athletics calendar, introducing more 'street meets', increase commercial revenue, empower national federations and encourage young people into the sport.

But it is the fight against banned drugs which is set to be front and centre of his reign.

Coe, who has been backed by Mo Farah to "change athletics", has promised to set up an independent anti-doping agency for the sport inside his first 100 days in office.

The IAAF has come under fierce attack amid allegations - which it vehemently denies - that it turned a blind eye to suspicious blood test results from hundreds of athletes and also blocked the publication of a report claiming a third of athletes at the 2011 World Championships in South Korea admitted doping.

Coe has been the most outspoken voice on the accusations the IAAF has ignored possible widespread drug use, calling them a "declaration of war" on the sport.

Despite the strong rebuttals, it is clear serious damage has been done, and is being done, to the credibility of the organisation and the sport as a whole, an issue which needs to be addressed urgently.

Bubka was re-elected as an IAAF vice-president at the Congress, which is taking place ahead of the start of the World Championships in the Chinese capital on Saturday.

Coe paid tribute to Bubka, Diack, his campaign team and his wife, adding: "I will be meeting her outside the main congress hall with a photograph of me, just to remind her what I look like."

He has worked tirelessly to garner support from countries around the world during his campaign, travelling around 700,000 kilometres across the globe

He targeted the smaller nations with his plan for an Olympic Athletics Dividend, providing at least USD 100,000 of extra funding over four years to all IAAF member federations.

Coe delivered a powerful speech to the Congress ahead of the vote in which he said: "There is no task in my life for which I've ever been better prepared, no job I've ever wanted to do more and with greater commitment."

His election was greeted with joy by marathon runner Paula Radcliffe, who tweeted: "Congratulations sebcoe The future of our sport is in good hands."