Bank of America's Merrill Lynch and Wells Fargo have been offering spot bitcoin exchange-traded funds to eligible wealth management clients, highlighting the growing popularity of the asset class.

The ETFs have been available to clients for weeks, a source familiar with Bank of America's plans told Reuters on Thursday.

This comes on the heels of the Securities and Exchange Commission's (SEC) landmark approval of such investment vehicles in January.

"Spot bitcoin ETFs are available for unsolicited purchases through an advisor with Wells Fargo Advisors or through our online WellsTrade platform." Wells Fargo said in an emailed statement on Thursday.

Spot bitcoin ETFs offer investors exposure to the world's largest cryptocurrency without directly holding it. After a decade-long tussle with the SEC, 11 such ETFs started trading in the United States last month.

The ETFs have opened up the asset class to new investors and reignited the excitement that had evaporated when prices collapsed in the "crypto winter" of 2022.

The growing popularity of such investments has even prompted some investors to swap out holdings in gold-backed ETFs. Bitcoin is often touted as the "digital gold".

"We remain convinced that bitcoin is on an 18-month path to $150,000 led by unprecedented institutional adoption," Bernstein analyst Gautam Chhugani said earlier this week. Bitcoin on Wednesday hit $60,000 for the first time in more than two years.

Bloomberg Law first reported BofA and Wells Fargo's moves earlier in the day.

In contrast, Vanguard — the largest provider of mutual funds — said it has no plans to make spot bitcoin ETFs available on its platform to its brokerage clients. (Reporting by Pritam Biswas, Niket Nishant and Jaiveer Singh Shekhawat in Bengaluru; Editing by Shilpi Majumdar and Maju Samuel)