Tessa Jowell, the minister for the Olympics, wants to change rules that bar women from competing in as many events as men by the 2012 Games.
Ms Jowell said it was wrong that, under Olympic and Paralympic regulations, men can take part in 40 more medal events than women – 164 compared to 124.
A rule change would allow women to compete in boxing and heavyweight wrestling and men in synchronised swimming and rhythmic gymnastics. Ms Jowell and the Sports minister, Gerry Sutcliffe, have written to the heads of UK Sport asking them to investigate a "gender discrepancy" and to press for equal opportunity at the London Games.
Ms Jowell said she had discussed the issue with the gold medalist Victoria Pendleton, who was only able to compete in one sprint cycle event at last year's Beijing Games while her teammate Chris Hoy won three golds.