His Excellency Akbar Al Baker Qatar Airways chief executive Akbar Al Baker speaks to the media during the Arabian Travel Market on May 6, 2015 in Dubai, United Arab Emirates. The SFO's investigation relates to Barclay's fundraising activities in 2008.
The Serious Fraud Office (SFO) allegedly wants Barclays to sign a Deferred Prosecution Agreement (DPAs).
DPAs can be struck to waive criminal prosecution in return for full co-operation or agreement on fines. The SFO is yet to sign its first DPA since it got the power to do so last year, but the tool is often used by US prosecutors.
Barcalys signed a DPA with US regulators in 2012 to settle an investigation into Libor rigging.
The SFO has been investigating "certain commercial arrangements between Barclays Bank and Qatar Holdings" since 2012.
In 2013, another watchdog, the Financial Conduct Authority, alleged in its own investigation that Barclays paid around £322 million ($500 million) to Qatari investors in return for a £4.6 billion ($7.15 billion) capital injection at the height of the 2008 financial meltdown.
Barclays paid a £50 million ($77 million) fine but said it would contest the findings.
Sky News said that "some bank directors" aren't keen on signing the new deal with the SFO, which was sent to the bank a few weeks ago.
Barclays and the SFO both declined to speak to Sky.