Leading virtual currency bitcoin on Wednesday traded above US$20,000 for the first time following a sustained run higher in recent weeks.

Just 12 years old, bitcoin reached a record-high US$20,398.50 before pulling back to US$20,145, which was still an intraday gain of nearly 4 per cent.

It has seen a meteoric rise since March, when it stood at US$5,000, spurred by online payments giant PayPal saying it would enable account holders to use cryptocurrency.

A number of central banks have meanwhile responded to the rise of cryptocurrencies and the dwindling global use of cash by announcing plans for bank-backed digital units.

Several central banks including those of China and Sweden – but also the US Federal Reserve – are also testing digital applications in response to Facebook’s recent moves to produce its own digital unit, Libra.

Unregulated by any central bank, bitcoin emerged as an attractive option for investors with an appetite for the exotic – although criminals have also seen its under-the-radar appeal.

Debate has meanwhile raged over the status of the digital asset, launched in late 2008, as to whether it should be seen as a form of money, an asset or a commodity.

After the unit surpassed US$1,000 for the first time in 2013, it increasingly began to attract the attention of financial institutions and has experienced wild price swings.