The Serious Fraud Office (SFO) has charged Barclays Bank PLC with "unlawful financial assistance" related to billions of pounds raised from Qatar in 2008.

The same charges were bought against Barclays PLC in June last year.

The move to charge Barclays Bank as well is significant because it holds the banking licence that allows it to operate in different countries.

So, if Barclays was found guilty, it could lose that crucial licence.

In 2008, to avoid a government bailout, Barclays took a £12bn loan from Qatar Holdings, which is owned by the state of Qatar.

Under that deal Barclays loaned £2.3bn back to Qatar Holdings.

The SFO alleges that loan was used either directly, or indirectly, to buy shares in Barclays, which the SFO says is "unlawful financial assistance".

In response, Barclays said: "Barclays PLC and Barclays Bank PLC intend to defend the respective charges brought against them.

"Barclays does not expect there to be an impact on its ability to serve its customers and clients as a consequence of the charge having been brought."

The emergency funds from Qatar allowed Barclays to avoid a government bailout in 2008 at a time when rivals Lloyds Banking Group and Royal Bank of Scotland were forced to rely on a taxpayer rescue.

Following a five-year investigation into the deal with Qatar Holdings, the SFO in June charged Barclays PLC and several former executives with conspiracy to commit fraud.

Former chief executive John Varley, former senior investment banker Roger Jenkins, Thomas Kalaris, a former chief executive of Barclays' wealth division, and Richard Boath, the ex-European head of financial institutions, were all charged in relation to that investigation.

The bank and its former bosses will face trial in 2019.

Barclays is the first British bank to face a criminal trial related to its conduct during the financial crisis.