Barclays has set aside an extra £700m to meet compensation claims for mis-selling payment protection insurance.
The news came as the bank said costs related to the sale of part of its Africa unit had pushed it into a £1.2bn loss in the first half of the year.
The sale of the Africa business was part of Barclays' plan to focus on the UK and US.
Stripping out the losses from the Africa sale, Barclays posted a 13% rise in group pre-tax profits to £2.34bn.
Barclays chief executive Jes Staley said: "Our business is now radically simplified, the restructuring is complete, our capital ratio is within our end-state target range, and, while we are also working to put conduct issues behind us, we can now focus on what matters most to our shareholders: improving group returns."
The money the bank has set aside to deal with PPI complaints was still open to review, it said. On Thursday, Lloyds also set aside a further £700m.
Analysis: Kevin Peachey, personal finance reporter
The PPI scandal is not only big - banks have set aside a total of nearly £40bn to pay compensation - it is also long-running.
Over the next few months the pace of it is likely to keep accelerating. The City regulator, the Financial Conduct Authority, will run a campaign to encourage those mis-sold PPI to make claims before the deadline of August 2019.
You can expect more activity too from the claims management companies touting for business through calls and texts. They take a cut of any payouts made to claimants who use their services.
Banks wanted a earlier deadline. They want to draw a line under this saga. It is almost impossible to judge how much PPI was mis-sold - so they will also hope these latest provisions have over-estimated the final bill.
Earlier this year, Barclays sold a near 34% stake in Barclays Africa Group, leaving it with just 15% of the business.
The company said the sale of the stake had led to a loss of £1.4bn, and it had also taken a £1.1bn charge on the sale.
Barclay's Africa Group said on Friday its half-year profit rose 7% driven by earnings growth in its local market and the rest of Africa and a strong performance in corporate banking.
In addition to Barclays' exit from Africa, the bank said it had run-down assets in its non-core division to below £25bn, enabling it to close the unit six months early.
Mr Staley said Barclays had completed "two critically important planks" of its strategy to get out of unwanted businesses.
Santander, also a giant in the UK banking market, reported results on Friday.
For the first six months of the year pre-tax profits in the UK were £1bn, little changed on the same period last year.
The firm said that it sees "greater uncertainty" and has concerns about the rest of this year and the start of 2018.
The lender said: "The labour market remains strong, but higher inflation, largely from the lower value of sterling, is now reducing households' real earnings.
"This is likely to result in lower consumer spending growth which, when combined with a potentially more challenging macro environment, adds a degree of caution to our outlook."
It took a £69m charge to cover claims for payment protection insurance compensation in the first six months of the year.
Santander also said net mortgage lending fell by £200m after it withdrew some of its most competitive rates at the end of last year.
The Banco Santander group as a whole saw second quarter net profit jump by 37% to £1.75bn euros (£1.5bn) helped by strong growth in South America.