Bank of New York Mellon said on Wednesday that fourth-quarter earnings fell 26 percent after the world's No. 1 custody bank reported lower forex volume and took a restructuring charge as part of a large-scale plan to make its operations more efficient.

BNY Mellon reported net income of $505 million, or 42 cents a share, compared with $679 million, or 54 cents a share, a year earlier. The results included a $107 million restructuring charge that reduced net income by 6 cents a share.

Chief Executive Officer Gerald Hassell said in a press release that general financial uncertainty in Europe and other parts of the globe depressed client activity, pressuring revenue.

Investment management and performance fees, for example, were $730 million, a decrease of 9 percent from a year earlier. BNY Mellon laid some of the blame on money market funds, whose miniscule yields have forced the company to waive fees to keep investors.

In the fourth quarter, foreign exchange revenue totaled $183 million. That was a decline of 11 percent from the year-ago period because of lower volume.

(Reporting By Tim McLaughlin; Editing by Lisa Von Ahn)