Coe, the chairman of London 2012, had been expected to stand if Diack kept his promise to step down when his current four-year term ended.

Diack's departune was expected to spark an election involving Coe, Ukraine's world pole vault record holder Sergey Bubka and possibly Nawal El Moutawakel, the 1984 Olympic 400 metres hurdles champion who is now a senior and influential member of the International Olympic Committee (IOC).

But Diack, a former Senegalese Government Minister who took over as President of the IAAF in November 1999 following the sudden death of Primo Nebiolo, now claims that he is being pressurised to continue in the role, which would see him in charge for the London 2012 Olympics, which coincides with the centenary of the founding of the IAAF.

He told insidethegames: "It's possible [I will stay] if I'm in good shape.

"Many people are asking me to do that, depending on my health."

Diack did offer some hope, though, that he would step down as he had promised after his last election on the eve of the 2007 World Championships in Osaka.

He said: "I will go if I have prepared some people to take over."

Coe, the 1980 and 1984 Olympic 1500m champion, and Bubka, the 1988 Olympic pole vault gold medallist, are both vice-presidents of the IAAF.

Both are among the most high-profile administrators in world sport.

The reputation of 52-year-old Coe, a former Conservative MP, has been enhanced by overseeing London's successful bid for the London 2012 Olympics and then his subsequent safe handling of the preparations.

Bubka, 45, is the President of the Ukraine Olympic Committee and member of the IOC, currently being head of the Coordination Commission for next year's inaugural Summer Youth Olympics in Singapore.

El Moutawakel's name as a possible candidate had been mentioned increasingly recently.

The former Moroccan Sports Minister, 47, is highly thought of after leading the IOC's Evaluation Commissions for the 2012 and 2016 Olympics.

She is also a long-time member of the IAAF's ruling Council.

For Coe, becoming President of the IAAF, would carry the added bonus of automatic membership of the IOC, something he covets.

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