BRUSSELS, July 28 (Reuters) - EU regulators said on Tuesday 28 July they would fine-tune antitrust rules on distribution deals between manufacturers and retailers due to the stronger power of big players and the increasing popularity of Internet sales. The current guidelines, which exempt companies from strict EU competition rules in some circumstances, expire in May 2010 and are expected to be renewed for another 10 years with revisions. The European Commission, competition watchdog of the 27-country European Union, said interested parties have until Sept. 28 to comment on its proposals.

The rules on supply and distribution agreements should not be fundamentally modified, it said.

"Two major developments have marked the ten-year period following the entry into force of the current rules: a further increase in large distributors' market power and sales on the Internet," the EU executive said in a statement.

Under the proposed changes, manufacturers and retailers can be exempted from antitrust rules only if their market share is below 30 percent. This exemption currently applies only to providers of goods and services. (Reporting by Foo Yun Chee; Editing by Dale Hudson)