SINGAPORE (Reuters) -The yen firmed on Monday after Japan’s ruling coalition lost its majority in the upper house as investors braced for a period of policy paralysis and market tumult in the world’s fourth-largest economy ahead of a deadline on tariff negotiations with the U.S. Prime Minister Shigeru Ishiba’s Liberal Democratic Party returned 47 seats, short of the 50 seats it needed to ensure a majority in the 248-seat upper chamber in an election where half the seats were up for grabs. While the ballot does not directly determine whether Ishiba’s administration will fall, it heaps political pressure on the embattled leader who also lost control of the more powerful lower house in October.