The head of the World Trade Organization said on Saturday she hoped that post-Brexit tensions between Britain and the European Union would not escalate into a trade war.

“I would really, really hope that a UK-EU trade war will not take place,” WTO Director-General Ngozi Okonjo-Iweala said in response to a question when speaking to reporters covering a Group of Seven leaders’ summit in southwestern England.

“With all the opportunities there are too for dialogue, I would be a little surprised if we ended up with a UK-EU trade war,” she said. “It’s too costly for both sides. This is not what the world needs right now.”