The IAAF called on the World Anti-Doping Agency (WADA) to adopt stronger penalties for doping, including a four-year ban for serious first-time violations.
"We remain convinced that strong penalties are an important cornerstone of an effective anti-doping campaign in general, and in athletics in particular," the International Association of Athletics Federations Congress said in a statement.
WADA currently has a two-year penalty for serious violations by initial offenders.
The agency is reviewing its anti-doping code and will adopt a revised one in November. It is unlikely to approve the changes sought by the IAAF.
Marathon champion Gharib pulls out
Two-times marathon champion Jaouad Gharib of Morocco has pulled out of the World Championships, organisers said.
"After having taken some extra time off after London due to a slight injury, he decided to forego the worlds," Eric Lilot, who manages the Moroccan, told organisers.
The 35-year-old won world titles in 2003 and 2005.