The proposed Transatlantic Trade and Investment Partnership (TTIP) deal between the U.S. and the European Union is facing real issues and it is going to take time, the secretary-general of the Organization for Economic Cooperation and Development (OECD) told CNBC on Saturday.
The deal would loosen the regulatory barriers to trade between the world's two largest trading blocs. U.S. President Barack Obama is in favor of the project, but U.S. Presidential candidate Donald Trump has been critical of multilateral trade deals that he says may harm U.S. workers and industries.
Angel Gurria, the head of the OECD, said TTIP was a win-win proposition, but that it was "so difficult and so important and that's why it's going to take time," in an interview with CNBC on the sidelines of the G-20 summit in China.
In recent weeks, European politicians have complained that talks to secure a deal are failing because their U.S. counterparts will not compromise sufficiently.
Gurria pointed to the upcoming U.S. Presidential elections and the anti-free trade rhetoric in the country as challenges, along with stagnant economic growth in Europe that might spur protectionism.
"We are only two months away from the U.S. election and again the mood in the U.S. is, at least from the speeches, very anti-free trade and at the same time in Europe, you have a very low growth period," he told CNBC.