Bitcoin fell sharply on Wednesday after the U.S. Securities and Exchange Commission (SEC) delayed a decision on a proposed bitcoin exchange-traded fund (ETF), which would have been the first financial product of its kind.

Cryptocurrency markets fell as a result. Bitcoin was down around 6 percent from 24 hours ago at 4:12 p.m. New York time, trading at just over $6,300, according to data from CoinDesk.

Investment firm VanEck teamed up with Solid X, a financial service company, earlier this year in a bid to launch an ETF that is backed by actual bitcoins rather than futures. An ETF is a financial product that tracks the price of an asset and is listed on an exchange. It means that investors don't actually have to buy the underlying asset.

ETF's are seen as a way for institutional investors to get into cryptocurrency investing in a safer way than buying bitcoin on a crypto-asset exchange.

This is VanEck's third attempt to push a bitcoin ETF through, having been rejected by the SEC twice previously. On this occasion, the SEC said that it is pushing out its decision until September 30.