Unveiling Tuesday's results, Barclays Chief Executive Antony Jenkins said Thursday's update "Will address issues underlying the performance challenges we have recently experienced, including positioning the investment bank for the new operating and regulatory environment."
Jason Napier, an analyst at Deutsche Bank, said Barclays' FICC results were the worst of its peers, and that overall, there was ample reason for Barclays to announce large-scale restructuring on Thursday.
"Revenues in the investment bank were very disappointing indeed. Barclays' management has been given all the reason required to embark on fundamental restructuring of the investment bank in particular. With the weakest FICC progression report so far, investors demand nothing less," Napier said in a research note on Tuesday.
Barclays has reported a swath of management changes in recent weeks, adding to speculation that it could announce significant job cuts and downscaling of struggling units on Thursday. Even prior to its latest weak results, Barclays had said it was planning cuts to its investment bank division, and warned it could make up to 12,000 cuts across the bank as a whole this year. Some media organizations are reporting that cuts could be up to 15,000, but Barclays declined to confirm or deny this.
Its recent restructuring announcements have focused on its investment bank, which has seen the resignations of several ex-Lehman Brothers staff, who were absorbed into Barclays when it acquired the failed bank's financial services firm in 2008.
Read MoreBarclays reorganizes management of investment bank
Last month, Barclays reported that Joe McGrath and Richard Taylor had been made co-heads of banking within the investment bank, with Eric Felder as head of markets.
The bank also announced that Joe Gold would replace former Lehman banker, Hugh (Skip) McGee, as chief executive officer of Barclays Americas.
Another member of the ex-Lehman coterie to go is Larry Wieseneck, the head of global distribution and structuring at Barclays, who will depart in June to "pursue other interests".
In addition, the Financial Times newspaper reported this week that Stuart Francis, the head of Barclays' technology banking business, was preparing to resign. He is also a Leman alumnus who worked under McGee.