Japan's central bank may face political pressure to keep interest rates low for longer than it wants, as opposition parties favoring tax cuts and loose monetary policy are expected to gain influence after a July 20 election.

Opinion surveys suggest Prime Minister Shigeru Ishiba's coalition may lose its majority in the Upper House of parliament, forcing it to court an array of smaller parties pushing for easier fiscal and monetary policy.

The governing bloc led by Ishiba's Liberal Democratic Party is already a minority in the more powerful Lower House, so a stalemate in both chambers could give opposition parties outsized influence in policy decisions.