Trump White House could dent US economy: Eastern Bank CIO

The likelihood of Donald Trump becoming the Republican presidential candidate compounds concerns about the U.S. economy's inability to kick into higher gear, Eastern Bank Chief Investment Officer Michael Tyler said Wednesday.

Trump moved decisively closer to the nomination on Tuesday after his most formidable rival, Texas Sen. Ted Cruz, suspended his campaign following the celebrity businessman's victory in the Indiana primary.

Tyler said the win adds to his concerns that central bank policy is proving incapable of producing growth in the United States and abroad.

"His impact on what markets might do is also somewhat concerning if you look at economic policies," Tyler told CNBC's "Squawk Box." "In particular, the dramatic tax cuts combined especially with the protectionist tariff increases I think could be really negative for the U.S. and global economy."

Trump has said he would threaten China, one of the country's top trading partners, with tariffs during trade negotiations.

Asked about anti-free-trade sentiment on the left, Tyler said Sen. Bernie Sanders faces a tougher path to the Democratic nomination than Hillary Clinton.

Clinton is more moderate than President Barack Obama, and more mainstream and accepted by Wall Street than Trump, he added.

Michael Zinn, UBS senior vice president for wealth management, said Trump injects uncertainty into the markets because he has offered few policy specifics, opting instead to rely on charisma thus far.

Trump's policies may become clearer as the Republican National Convention approaches and more Republicans coalesce around him, he said. At that point, Wall Street can determine how serious his agenda is and make up its mind, he added.

"For now, we've got more uncertainty," he told "Squawk Box."