Germany's Economy Minister Philipp Roesler said he supports a short-selling ban across the G7, going further than his country's finance minister, who has backed such a ban only in Europe.
Roesler said "it is good and proper that other European countries have now banned short-selling," in an interview with the Welt am Sonntag newspaper released on Saturday.
"But that is not enough," he added. "It's necessary that highly speculative financial transactions be banned not only in Europe, but at the level of the G7 states."
He said the issue should be "on the agenda at the next G7 summit".
On Friday, Germany called for a European ban on some short-selling of shares after four of its EU partners banned the speculative practice for two weeks to combat uncertainty rocking markets.
Berlin backed measures by France, Italy, Spain and Belgium to stop short-selling of bank shares but urged Europe to go further to calm the waters.
The German finance ministry wanted to see "a broad short-selling ban in Europe," a ministry spokesman said Friday.
There are no indications that a ban on the practice is likely to be imposed across the G7 markets -- which include Britain, Canada, Germany, France, Italy, Japan and the US -- and Britain has distanced itself from the idea.
oesler was previously reprimanded by Finance Minister Wolfgang Schaeuble after he tabled his own ideas for governing the eurozone.
Berlin has struggled to speak with a unified voice on the economic crisis plaguing Europe, which analysts say highlights strains in the ruling coalition made up of Chancellor Angela Merkel's conservative CDU-CSU party and the liberal FDP party, of which Roesler is a member.