LONDON  In his first full day in Europe, President Obama conceded Wednesday that the United States had “some accounting to do” for failures that led to the world’s financial crisis, even as he tried to brush past heavy pressure from Germany and France to accept global financial regulations that could reach well inside American borders.

Speaking on the eve of a summit meeting here to address the financial crisis, Mr. Obama acknowledged that regulatory failures in the United States had a role in the meltdown, but he urged world leaders to focus on solutions rather than on placing blame. He also cautioned that the United States was unlikely to return to its role as a “voracious consumer market,” and he urged other nations to do more to revive growth in their home markets.

Despite calls for unity from Mr. Obama and the British prime minister, Gordon Brown, the host of the Group of 20 meeting that will formally begin Thursday, a rift intensified over Anglo-American calls for greater fiscal stimulus spending and French and German demands for more intrusive global regulation of financial institutions.

While President Nicolas Sarkozy of France did not repeat an earlier threat to walk out of the conference  “I just got here,” he joked  he made it clear he would reject an agreement that puts off stringent new regulations on banks, tax havens, and hedge funds.