The world's rich economies said they would take a tougher stance on fighting money laundering and tax evasion but promised little in the way of specific new action at the end of a two-day summit on Tuesday.
The Group of Eight leaders signed up for a string of aims including improved transparency about who owns shell companies and more information-sharing between tax authorities.
Under pressure from austerity-weary voters, lawmakers have focused increasingly on tax dodges. More than 50 countries have agreed to a new protocol on tax data sharing since 2011.
Cameron said his proposal that firms report profits on a country-by-country basis could help expose corporate profit shifting into low-tax states.
The G8 leaders, meeting in Northern Ireland, said their governments would draw up action plans for collecting and sharing information on who really owns companies, making it harder to set up Russian-doll type structures.
The United States pledged to keep on pressing for legislation to cut down on the criminal use of shell companies.
"The credibility of this depends on the ability of the White House to advance legislation," said Gavin Hayman, director of campaigns at anti-corruption group Global Witness.
The United States pointed out it was planning to require banks to understand who their customers actually are and provide information for law enforcement and tax authorities.
A frequent critic of tax havens, the United States has come under fire from campaigners for the low transparency requirements around ownership of corporate entities registered in some U.S. states such as Delaware.
Tax campaigners had called for companies to be forced to make public their profits, revenues and tax payments for every country where they operate. That could deter accountants from building contrived arrangements to keep tax low. Business groups remained against such a move.
"We continue to have real doubts about the utility of any rules requiring the release of vast amounts of raw data to the public," Andrew Wilson, UK Director of the International Chamber of Commerce said in a statement.
The G8 leaders also called on the Organisation for Economic Co-operation and Development (OECD), which advises rich nations on economic policies, to come up with a way that could require multinational corporations to report profits and tax payments to authorities on a country-by-country basis
Some developing nations complain they struggle to get information about companies' operations in other countries, so the measure could help them cut profit shifting.
The OECD is working on a broader program to tackle tax avoidance under the auspices of the Group of 20 comprising the leading developed and developing economies.
What is described above at the G8 is the wave of the future. All countries will within the next few years be sharing tax data, etc. with each other. Now is the time to get into legal compliance with your tax filings before it is too late. If you need help email us at ddnelson@gmail.com .