MEXICO CITY, Jan 15 (Reuters) - Mexico has identified about 270 multinational companies that may be using aggressive tax planning to shirk their fiscal responsibilities in Latin America's No. 2 economy, the head of the country's tax collection office said on Wednesday.
Mexico, which passed a reform aimed at boosting the tax take last year, has the weakest tax revenues in the 34-nation Organization for Economic Co-operation and Development (OECD), due to both evasion and a small tax base.
The reform, which imposes new taxes on the wealthy and levies on junk food and sugary beverages, is forecast to boost government revenue by more than 1 percent of gross domestic product this year and by more than 2.5 percent of GDP by 2018.
Authorities are also stepping up enforcement of existing tax rules, with new scrutiny on multinational companies.
"We have a hypothesis that there could be 270 groups that are multinational, trans-national companies that could be using aggressive fiscal planning," Aristoteles Nunez, head of tax collection office SAT, told reporters at an event in Mexico City.
"We're already in touch with many of these companies to learn how they are conducting their operations, through coordinated efforts with other countries' tax administrators, to find out if they are actually carrying out aggressive tax planning," he said.
Nunez added that authorities would conduct an audit if enough information could not be obtained through other means.
Excluding revenue from state oil firm Pemex, Mexico's government collects taxes worth only about 10 percent of its gross domestic product GDP, far less than its main peers in Latin America.
The International Monetary Fund has urged Mexico to consider further efforts to boost the country's non-oil income, after last year's tax reform fell short of expectations.
A global financial integrity study released in December shows crime, corruption and tax evasion drained $462 billion from Mexico's economy in 2011, making it the world's third- biggest exporter of illicit capital, behind China and Russia.
In September, Group of 20 countries pledged to help developing countries fight tax evasion by assisting them in tracking funds their citizens hide in tax havens through an information exchange starting in late 2015.
(Reporting by Alexandra Alper; Editing by Dan Grebler)