** J.P. Morgan says a prolonged trade war or spike in tariffs would be a major negative for property and casualty insurers, but a manageable event for life insurers

** U.S. President Donald Trump on Saturday ordered sweeping tariffs on Mexico, Canada and China, igniting fears of a trade war that could hit global growth

** Brokerage says higher material costs would be a key negative for most P&C insurers as Mexico and Canada account for over half of auto parts imports to the U.S.

** Personal lines insurers such as Allstate ALL.N and Progressive PGR.N are especially susceptible to sustained high tariffs on imports from Mexico and Canada - JPM

** JPM says that while a prolonged trade war has negative implications for life insurers to the extent it pressures equity markets and the economy, they are more insulated than many other sectors

** Higher rates would be a tailwind for companies with elevated exposure to interest rate sensitive businesses and modest exposure to equity investments

** Globe Life's GL.N business mix makes it best positioned to cope with a prolonged trade war among major life insurers - JPM

(Reporting by Arasu Kannagi Basil in Bengaluru)

((ArasuKannagi.Basil@thomsonreuters.com;))