美官员：欧洲试图暗中破坏美俄领导人会晤以来取得的进展

Group 1 - The core viewpoint of the article indicates that European leaders are attempting to undermine the progress made since the U.S.-Russia leaders' meeting in Alaska, despite publicly supporting U.S. President Trump's efforts to resolve the Ukraine crisis [1] - White House officials assert that European leaders cannot delay the conflict while presenting unreasonable expectations and expecting the U.S. to bear the costs [1] - A senior White House official mentioned that the U.S. is seriously considering temporarily withdrawing from diplomatic mediation until one or both parties show greater flexibility [1]