The Greek debt drama may be roiling securities minute to minute, but in the big picture, markets are resilient enough to absorb a shock, Michael Zinn, senior vice president of wealth management and a portfolio manager at UBS, said Tuesday.
U.S. stock futures pointed to a higher open after tumbling Monday amid uncertainty over the situation in Greece. The fell 2 percent in the previous session, wiping out its gains for the year. The Dow Jones industrial average plummeted 350 points, or 1.95 percent, in its worst trading day since October.
Stocks were broadly lower in Europe on Monday. They remained under pressure Tuesday, but came off their lows on a report that negotiations between Greece and European creditors could resume.
"This is taking place not in October, where we saw a bit of weakness. This is taking place where we're seeing economic resilience," he told CNBC's "Squawk Box." "We're seeing steepening yield curves, we're seeing good economic data and we're seeing good optimism. So I think in that context, the markets are better placed to absorb some kind of shock."
Greek officials have warned the country is unable to pay 1.6 billion euros ($1.7 billion) due to the International Monetary Fund by 6 p.m. EDT on Tuesday, after reform-for-aid talks with creditors broke down over the weekend.
The country's bailout fund—called the European Financial Stability Facility—is due to expire at the end of the day, after an extension was rejected by creditors.
Overnight, European Commission President Jean-Claude Juncker made a last-minute offer to Athens, a spokesperson for the commission said Tuesday.
Greek media reported early Tuesday that the government would return to the negotiating table, although this was unconfirmed. Greek Prime Minister Alexis Tsipras rejected the same proposals from creditors this past weekend and called a snap referendum on the bailout program and austerity measures.
Zinn said it's important to keep in mind the larger context in which the negotiations are taking place.
"This isn't just a referendum on Greece. This is a referendum on broader global economies, and the degree to which Greece impacts broader global economies is going to depend on the degree to which those economies are strong," he said.
The European Central Bank can now serve as a backstop because it's in better form than it was four years ago, Joseph LaVorgna, chief U.S. economist at Deutsche Bank, told "Squawk Box." Greece has also been ring-fenced because the private sector holds little Greek debt these days, he added.
Financial services firm Allianz's expectation is for more volatility in the near term, said Kristina Hooper, head of U.S. capital markets research and strategy. That could be a buying opportunity, especially for those with a long investment time horizon and who are underexposed to equities, she said.
"Greece has been an issue on and off for years now. But what's changed is the ECB," she told "Squawk Box." "It seems like a far more potent central bank today after Mario Draghi's pledge in 2013 to do whatever it takes after it initiated [quantitative easing]," she said.
Despite impending interest rate tightening in the United States, the global environment of suppressed rates has changed the risk-reward profile for asset classes, she added.
"Bonds are just not attractive, sovereign debt is not attractive, core bonds are not attractive. Stocks are in many ways the least dirty shirt," she said.
Investors with at least a 10-year investment window should probably place at least 60 percent of their money, and perhaps as much as 80 percent, in stocks, she said.
Hooper also recommends diversifying across geographies. While U.S. stocks may deliver an upside surprise because companies have managed expectations, she said valuations "are not screaming buys in the U.S."
Meanwhile, European valuations are currently attractive, and once the market moves past the Greek headwinds, they could become even more attractive, she said.
—CNBC's Holly Ellyatt contributed to this story.