The Serious Fraud Office (SFO) has charged Barclays Bank over a 3 billion US dollar (£2.2 billion) loan given to the State of Qatar as part of a side deal linked to its emergency fundraising in 2008.
It extends a charge brought against the parent firm for "unlawful financial assistance" last July.
At the time, the SFO had not yet decided whether to charge the Barclays Bank unit over the loan as well. Barclays Bank has now been charged with the same offence.
Both Barclays and its bank unit have said they will defend themselves against the charges.
"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 company said in a statement.
The emergency fundraising at the centre of the SFO case allowed Barclays to avoid the fate of its bailed-out rivals Lloyds Banking Group and Royal Bank of Scotland.
Barclays pulled off an £11.8 billion fundraising package from Qatari backers and other investors in 2008 to sidestep the need for a Government rescue, which left Lloyds and RBS part-nationalised.
Money was pumped in by State-backed Qatari investors, as well as Abu Dhabi royals and investors from Singapore.
But the way the bank secured the Qatari investments has since been mired in controversy.
That included a 3 billion US dollar (£2.2 billion) loan made to the State of Qatar acting through the Ministry of Economy and Finance in November 2008.
After a five-year investigation into the events surrounding the cash call, the SFO last summer brought charges of conspiracy to commit fraud against Barclays itself, as well as a string of former executives.
It marked the first criminal charges to be brought in the UK against a bank and its former executives for activities during the financial crisis.
The SFO said on Monday that a date for the first court appearance in relation to the charge against Barclays Bank will be "set in due course".