LONDON — The danger of a systemic banking failure has passed and the worst of the credit crisis is over, the chief executive officer of Barclays’, John Varley, said yesterday.

Announcing a 33% fall in first-half profits to 2.75 billion pounds, Mr. Varley accepted that “the world ahead is not going to be an easy place,” but said: “The moment of greatest potential stress is now behind us.”

“The steps taken by the Bank of England, the U.S. Federal Reserve, and the European Central Bank have significantly alleviated the risks. Confidence in the system is returning.”

He cited as proof falling three-month interbank lending rates, which are almost 20 basis points below last month at 5.78%.

Continuing the comparatively upbeat tone, he added: “The world of the next 12 months will be one of economic slowdown but not of widespread recession.”

Barclays has written down 2.8 billion pounds of its “toxic” assets this year on top of 2.3 billion pounds in 2007.

However, analysts are not reassured. Keefe, Bruyette & Woods said there would be “continued questioning over the prudence of Barclays writedowns.” Citigroup has warned that it might need to take an extra 9 billion pounds.

Questions have arisen because different lenders account for assets in different ways. Unlike Royal Bank of Scotland, Barclays does not write down its 9.22 billion pounds leveraged finance portfolio.

Mr. Varley said that although “the important thing is to be consistent” internally, “it is simplistic to say everyone should do the same thing.”

Finance director Chris Lucas, rejecting the idea of a consistent industry approach, said: “Because people’s motivations differ, therefore the accounting has to differ.”

Barclays stressed that it is financially robust, with a pro-forma core tier one capital ratio of 6.3% after its recent fund-raising of 4.5 billion pounds. Half of the capital will maintain the ratio above 5.25% and half is for future growth. Mr. Varley said: “The natural line of advance is organic, but it would be foolish of us to rule out acquisitions.”

All Barclays’ businesses were profitable, with the British retail bank — which accounted for 26% of net new British mortgage lending in the half — improving profits by 7% to 690 million pounds as bad debt charges rose just 11 million pounds to 288 million pounds. Impairments for the whole group climbed 40% to 1.34 billion pounds, largely due to Spain and South Africa. At Barclays Capital, the investment bank, profits slumped 68% to pounds 524 million after the writedowns.