The world's biggest wealth manager says it's time to sell stocks

London(CNN Business) Happy Tuesday. A version of this story first appeared in CNN Business' Before the Bell newsletter. Not a subscriber? You can sign up right here.

For the first time since the eurozone crisis, the world's biggest wealth manager is bearish on stocks.

In a note to investors, UBS Wealth Management Chief Investment Officer Mark Haefele said that the group, which manages more than $2.4 trillion, has shifted to an "underweight" recommendation on equities.

The bank advised its wealthy clients to lower the proportion of stocks in their portfolios following President Donald Trump's decision to raise tariffs on all exports from China by 5% last Friday.

Here's why: "The US-China trade dispute has escalated in recent days, raising the risk of a cycle of retaliation that undermines global growth and equities markets," Haefele said. "That justifies a reduction in risk in our portfolios in order to lower our exposure to an uncertain political environment."

There's no arguing that geopolitics have sent stocks on a wild ride in the past month, largely driven by the president's haphazard moves on trade. Take a look.

Haefele said UBS (UBS) still thinks the United States can avoid a recession in 2020, helped by additional easing from the Federal Reserve and strong consumer spending.

And he cautioned that investors shouldn't sell stocks "as if they were preparing for a typical recession or the next Great Financial Crisis."

But UBS makes clear it does not see the current environment improving. "Downside risks are increasing for both the global economy and markets," Haefele said.

Watch this space: The leaders of Corporate America are also selling stocks, my CNN Business colleague Matt Egan reports from New York.

Corporate insiders have sold an average of $600 million in stocks per day in August, according to TrimTabs Investment Research, which tracks stock market liquidity. August is on track to the be the fifth month of the year in which insider selling tops $10 billion.

Read more: Insiders are selling stock like it's 2007

Here's our reality check on US consumers

Readers of this newsletter know that market bulls have been pointing to the strength of the US consumer as evidence that the economy has more runtime.

Retail sales in July beat estimates. And Walmart (WMT), seen as a bellwether of consumer spending, raised its guidance for the rest of the year. Such resilience, the thinking goes, is enough to offset some of the problems we're seeing in the manufacturing sector.

The question now: Can consumers keep holding up their end of the bargain?

We'll get fresh evidence on Tuesday, when the Conference Board releases its Consumer Confidence Index for August. The index rebounded in July after a sharp decline in June, driven by an escalation in trade tensions.

Investor insight: A recent University of Michigan survey showed that sentiment declined in early August. Investors will want to know if the Conference Board data mirrors that trend.

Up next

It's another light day for earnings, though investors in consumer staples may watch J.M. Smucker (SJM), which reports before the US market open.

Also today:

• The S&P Case-Shiller Home Price Index for June arrives at 9 a.m. ET.
• The US consumer confidence reading for August hits at 10 a.m. ET.

Coming tomorrow: How has Tiffany & Co. fared amid weak global growth?