WASHINGTON, May 18 (Reuters) - Vice President Kamala Harris and top White House economic adviser Lael Brainard said on Thursday that a default on the U.S. debt of $31.4 trillion would throw the American economy into a recession. In a conference call for Democratic activists, Harris and Brainard urged them to contact lawmakers to express opposition to a debt default that could be less than two weeks away. "A debt default could trigger a recession," she said. Negotiators for the White House and congressional Republicans met again on Capitol Hill to discuss their search for common ground on lifting the $31.4 trillion debt ceiling, and plan to meet again on Friday, a White House official said. Brainard said the administration's goal, in its talks with House Speaker Kevin McCarthy's team, is to work toward a reasonable, bipartisan budget agreement.

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