Martin Schulz, president of the European parliament, has warned that revelations of tax evasion by major companies were leading to a loss of trust among the European public.
Speaking to CNBC in Brussels, Schulz said the issue could lead to "very difficult social problems" in Europe if tax laws were not "transparent."
Tax evasion is expected to be high on the agenda as EU leaders prepare to meet at the European Council Summit on Wednesday in Brussels. A number of high-profile companies such as tech giants Google and Apple, coffee chain Starbucks and online retailer Amazon have come under the spotlight for alleged tax avoidance.
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"Tax evasion is the core of the debate because it is a question of solidarity. On the one hand, taxpayers are asked to pay for the enormous losses of the banking system or to save countries [or] make sacrifices on their pensions and salaries and they see that rich people can take their money out of Europe and into tax havens," Schulz said.