The conflict in the Middle East will have "ripple effects that extend far beyond the region", JPMorgan Chase's CEO Jamie Dimon warned in an internal memo to employees seen by Reuters.

The deadliest attack on civilians in Israeli history on Saturday has led to a dramatic escalation of violence in the region. The Israeli death toll has risen to more than 1,300, according to public broadcaster Kan, while Gaza authorities said more than 1,400 Palestinians have been killed.

The attack could prompt "an increase in antisemitism and Islamophobia around the globe", Dimon said, adding that the bank was working closely with the U.S. and international government agencies to guarantee the safety of its employees.

Reuters reported earlier this week that JPMorgan told its more than 200 employees in Israel to work from home.

The bank is making an initial contribution of $1 million towards relief efforts and will be matching employees' donations, according to the memo.

Separately, credit card giant American Express committed $1.5 million in donations to Israel and said it would match employees' contributions to all eligible non-profit organizations.

(Reporting by Niket Nishant in Bengaluru; Editing by Shilpi Majumdar)