"This is having a chilling effect on our economy. Every day that it goes on unresolved is a day that's not good for our economic prospects," Cameron said after the Group of 20 nations meeting ended this week in Cannes, France.
"The world can't wait for the eurozone to go through endless questions and changes about this," Cameron said, The Daily Telegraph reported Saturday.
The G20 meeting ended primarily with an impasse, as neither cash-rich countries such as China and Russia nor the stalwart United States agreed to pump money into the fund set up to help debt-burdened eurozone countries.
Furthermore, German Chancellor Angela Merkel said the European Commission was having trouble coming up with funds from its own members.
"There really are hardly any countries here that said they will join up," Merkel said referring to expansion of the European Financial Stability Facility.
Last week, European leaders agreed to increase the EFSF to a leveraged $1.4 trillion war chest to support the euro, which is the currency shared by 17 countries.
The move was applauded around the world by investors, as measured by stocks that soared in Asia, the United States and Europe.
In Cannes, however, President Obama said, "What is ultimately important is to have a strong signal from Europe that they are standing behind the euro," explaining his reasoning for not committing more U.S. funds to the International Monetary Fund, which would be an indirect contribution to Europe.