By Nell Mackenzie, Stella Qiu and Rae WeeLONDON (Reuters) -World shares were in a cautious mood on Monday and Wall Street futures lay flat as stalled U. President Joe Biden and House Republican Speaker Kevin McCarthy will meet to discuss the debt ceiling on Monday, less than two weeks before a June 1 deadline after which Treasury expects the federal government will struggle to pay its debts. However, in order to maintain the high level of discourse we’ve all come to value and expect, please keep the following criteria in mind:  Are you sure you want to block %USER_NAME%?Block List