Standard Chartered Plc’s Bill Winters, who runs one of the biggest trade-finance banks in the world, said U.S. President Donald Trump risks reversing decades of progress in globalization if he attacks the World Trade Organization or starts imposing border taxes on trading partners.

Deep antagonism between the U.S. and a given trading partner, or “a fundamental assault on the multilateral trading systems, the WTO most obviously—those would be very bad outcomes,” Winters, the former head of JPMorgan Chase & Co.’s investment bank, told reporters at Standard Chartered’s main office in Karachi, Pakistan, on Thursday. “If the WTO loses its effectiveness as a mediating trading body, it’ll be undoing 30 years of progress in global trade.”

Winters, Standard Chartered’s 55-year-old chief executive officer, said last month that the bank was “war-gaming” trade disruptions that some of Trump’s policies could cause. The Asia-focused lender has a lot staked on the future of trade, as its executives are attempting to persuade investors they can restore revenue growth after years of missing targets and incurring fines for misconduct.

The CEO reiterated he didn’t think a full-blown trade war was likely. He said the most probable actions taken by the U.S. would include tariffs or other barriers against specific countries such as China and Mexico, causing little knock-on impact to the global economy. However, he said it’s hard to predict what could happen given the rhetoric used by Trump and his top advisers.

‘Bilateral Spat’

“We could end up with something that’s closer to the narrative we heard during the election, especially with a much more aggressive border adjustment type system that has embedded in it substantial tariff barriers—we’re talking 20 percent, that’s very material,” Winters said. “Or a bilateral spat that gets out of control” with one of the U.S.’s major trading partners, he said.

If Trump does start a fight with China over trade, investment would be driven out of the U.S. and Europe and into Asia, where China would take the lead role in a super-regional trade bloc, Winters said Feb. 24. China’s standing in Asia was already bolstered when the U.S. pulled out of the Trans-Pacific Partnership, he said.

“In the short term those sorts of scenarios could be bad for us,” Winters said. “Can the rest of intra-Asian, South Asian, African, Middle East trade offset the decrease from the U.S.? No. The U.S. is the biggest market in the world by far, certainly the biggest importer in the world by far. It would be damaging to the world economy, it would be damaging to the economies in this region.”

Pakistan Risks

Winters was visiting Pakistan for the first time since taking the helm at Standard Chartered in 2015. He said the bank is looking to take advantage of business opportunities from increased consumer spending, as Pakistan heads into an election next year, as well from power and infrastructure projects. But those opportunities will be offset by the bank’s “extremely high” spending on compliance in the country, Winters said.

In June, the lender’s Pakistan head Shazad Dada highlighted banking risks in the South Asian nation from “suspicious money” related to terrorism financing, corruption and human trafficking being channeled through lenders. There are also concerns about the lack of transparency with the terms of Chinese loans for projects in Pakistan.

“For us to be involved in a project it’ll have to be perfectly transparent to us, there’s no question about that,” Winters said. “We’re not forming a view on the things we don’t need to be directly involved with. If we thought there was something fundamentally corrupt about the arrangements of the government of course we’d have concern, but we certainly see no indication of that.”

Standard Chartered has been operating under a deferred prosecution agreement with U.S. authorities since 2012, when it was fined $667 million for violating U.S. sanctions on doing business with Iran.

After speaking with local officials and lunching with clients in Karachi, the country’s commercial hub, Winters said he’s more confident about Pakistan’s prospects than many other markets as China pumps in about $55 billion of funds and loans to finance badly needed infrastructure projects in the nation of 200 million people.

Pakistan’s economic growth rate of about 5 percent wasn’t reflective of its potential, which is above 7 percent, he said. That can be reached if the government can address its infrastructure bottlenecks and continue to improve security, which has traditionally deterred many foreign investors, Winters said.

“When I visit many other markets I don’t get the same sense of optimism,” he said. At the same time “I’m not sure if people are queuing up,” but “Pakistan has now demonstrated three solid years of economic growth, coincided with a drop in commodity prices. So there’s a question, how much of the underlying economic momentum is coming as a result of the lower fuel bill?”