Monzo, a UK digital-only bank, is closing in on new funding led by US-based Thrive Capital

Updated article to clarify the pending round is a Series C

Updated again with info that British pop star Tom Odell may also be investing

Monzo, one of a number of new digital-only, or so-called “challenger,” banks in the U.K. aiming to re-invent the current account, is closing in on new Series C funding, which could be announced as early as this week.

According to multiple sources, U.S.-based Thrive Capital is leading the round. However, I’ve been unable to peg the exact investment amount, with one source telling me it is around £30 million, while another says it is less than that but certainly more than £20 million. I also understand Monzo is planning to launch a second equity crowdfunding campaign shortly, too.

“We’re not able to comment right now,” Monzo co-founder and CEO Tom Blomfield told me when I asked for confirmation of the startup’s new funding and lead investor.

Interestingly, I’m hearing that British singer/song writer Tom Odell may also be investing in Monzo. That’s particularly intriguing, as Sky News reports that rapper, producer and tech entrepreneur is pairing up with and possibly investing in Atom, another U.K.-based challenger bank.

Noteworthy, Monzo wouldn’t be the first European fintech to receive backing from New York-headquartered Thrive Capital. The VC firm, founded by Josh Kushner, recently led a €30 million Series C round in German fintech Raisin, which offers pan-European savings accounts.

Monzo (previously Mondo) is building a digital-only bank, or “smart bank,” as Blomfield calls it, and last August was granted a U.K. banking licence “with restrictions” by the U.K. regulators FCA and PRA as it prepares to launch a full current account later this year.

As it exists today, Monzo’s more than 100,000 users get access to a pre-paid MasterCard and accompanying iOS and Android apps. It offers the ability to do things like track your spending in real time, view geolocation-marked transactions on a map, view spending by category and get a graphical timeline of your overall expenditure.

The startup has previously raised £12.8 million in funding, the majority of which came from early-stage London VC Passion Capital, in addition to an equity crowdfunding round. The most recent £4.8 million “bridge funding,” which was announced in October, valued Monzo at £50 million.

Meanwhile, Monzo was rumored late last year to have turned down a substantial acquisition offer from an incumbent bank, which Blomfield confirmed last week in an interview with TechCrunch.

Explaining the reason for declining the offer, he said: “It’s never just the money, the money comes with strings and they’re really, really onerous…,” citing legacy IT, culture and thinking. “It just stops you taking risks, fundamentally, stops you innovating, that’s the real problem.”

In addition, Blomfield told TechCrunch that, although you can never rule it out, selling early is the startup bank equivalent to a bailout plan: “It means you haven’t accomplished what you set out to do.”

The company’s pending Series C funding shows that Blomfield and the rest of the Monzo team have a long way to go yet.

Listen to TechCrunch’s recent interview with Monzo co-founder Tom Blomfield