The number of global fallen angels soared to the highest level since 2015, with the list of potential fallen angels exceeding the global financial crisis count, S&P Global Ratings said.

Global fallen angels spiked to 23 as of April 13 from two at the end of January due to the coronavirus pandemic and low oil prices, S&P Global Ratings said. Fallen angels are companies whose credit rating has been cut to below investment grade.

The midstream and refining sector led with seven issuers downgraded to speculative grade, followed by the oil and gas sector with four and retail and restaurants with three.

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"While investment-grade issuers typically are able to withstand considerably more macro and event-driven stress than their speculative-grade counterparts, the COVID-19 pandemic and oil price shocks have resulted in a marked increase in fallen angels," according to S&P Global Ratings.

Delta Air Lines Inc., Ford Motor Co., Occidental Petroleum Corp., Marks & Spencer Group PLC and Esselunga SpA, among others, saw their ratings lowered to speculative grade earlier this year.

The list of potential fallen angels, companies rated BBB- with negative outlooks or companies with ratings on CreditWatch with negative implications, reached 96, surpassing the count of 82 during the global financial crisis.

Among potential fallen angels, media and entertainment is the most exposed sector to the current challenging conditions, with restrictions on travel and consumer activity causing significant declines in revenue for lodging and leisure companies, the rating agency said.

Ten new potential fallen angels from the oil and gas sector were added. British Airways PLC and Hyatt Hotels Corp. are also on the potential fallen angels list.