Barclays announced that its pre-tax profit for 2012 plunged 95.8% from £5.9 billion to £246 million, reflecting the cost of compensating customers for the mis-selling of pension protection insurance and interest rate swaps as well as a change in value of its own debt.
The London-based bank is a large employer in Glasgow, where it has a major back office unit employing about 2200 people, with others based at 22 branches and five corporate banking offices across Scotland.
These operations are unlikely to be affected by the job cuts, with the axe falling primarily on investment bankers and bank branches on the continent and in Asia.
Mr Jenkins, who succeeded Bob Diamond in August in the wake of a £290m penalty for attempting to manipulate key interest rates, confirmed that the bank will withdraw from controversial activities such as trading in food and aggressive tax planning. He said: "Barclays is changing. There will be no going back to the old ways of doing things.
"We get it. We are changing the way we do business."
A review of Barclays' 75 business units will see it leave four and overhaul or sell another 32.
Mr Jenkins plans to focus on activities in Britain, the United States and Africa, and reduce the bank's presence in continental Europe and Asia.
Of the job cuts, 1800 are pencilled in for its investment bank, most of which have already been axed since the start of the year.
Another 1900 will come from its retail and business banking arm in Europe where one-third of branches will close. Barclays revealed its bonus pool for 2012 fell 13.8% to £1.9bn.
The average group employee saw their payout fall 13% to £13,300 and for those in the investment bank by 17% to £54,100.
But the payout still dwarfs the £733m handed out in dividends to shareholders over the year.
The bank announced a final cash dividend for 2012 of 3.5p per share to be paid on March 15.
Mr Jenkins said: "We need to give our investors a bigger share of the income we generate.
"We need to challenge the perception that performance-related pay is de facto guaranteed deposit performance."
But he played down the likelihood of a change in the short-term. "It is a journey and it will take time. It is not in our shareholders' interests to radically reduce the amount of money we pay in variable compensation if it leads to talent leaving the organisation."
Analysts concluded that Mr Jenkins' reforms will do little to hinder the bank's investment banking arm, which saw pre-tax profit soar 37% to £4bn in 2012.
This prompted a 25.85p or 8.57% leap in its share price to 327.35p despite a warning from Mr Jenkins that Barclays' earnings will be hit in 2013 by restructuring costs.
Marc Kimsey, senior trader at Accendo Markets, said: "Barclays delivered exactly what the trading floor wanted – a solid set of numbers, aggressive cost-cutting plans and a reiteration of the strategic overhaul. This draws a line under the legacy issues that have tainted the bank in recent months, will please shareholders, and go some way to improving the company's image."
Excluding one-off items such as a £1.6bn provision for PPI and £850m for interest rate hedging compensation, on an adjusted basis Barclays' profits rose by 26% to £7.05bn.
Barclays also revealed that it is a defendant in a class action in the US over its role in the manipulation of Libor interest rates, alongside four of its current and former directors.