American companies will become even bigger buyers of bonds sold by their peers as negative interest rates worldwide intensify pressure on them to deploy their $4 trillion cash pile, according to Citigroup Inc.

“In their search for yield, companies are likely to increase their allocation toward one- to five-year corporate bonds rated A or higher,” said Ajay Khorana, global head of Citigroup's financial strategy and solutions group.

During the past two years companies have purchased as much as 15 percent of all new A-rated corporate bonds with a maturity of one to five years, according to Khorana. That's more than pension funds, banks, or insurance companies, as treasurers search for places to invest record amounts of cash at a time when yields are evaporating on safer investments such as Treasuries.

“This pressure will be acutely felt by many U.S. multinationals who, for tax reasons, keep large cash balances invested in short-term securities through their overseas subsidiaries,” Citigroup bankers led by Khorana wrote in a report published by the banks financial strategy and solutions group.

Investment-grade companies in the U.S. have sold $302 billion of bonds in 2016 after issuing a record $1.3 trillion of debt in all of 2015, according to data compiled by Bloomberg.

Companies will also look to buy more sovereign and supranational debt, Khorana said.

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