Brazilian President Michel Temer has promised next month's Olympic Games will show the world "one of the major global economies at work in a mature democracy" in a special welcome message designed to alleviate growing fears with just 30 days to go until the Opening Ceremony of Rio 2016.

International Association of Athletics Federations (IAAF) President Sebastian Coe has been accused of being aware of corruption at the heart of the world governing body before his election last August and he accepted advice from disgraced official Papa Diack during his successful campaign.