Legendary investor Howard Marks has warned that a fully fledged trade war will be a "bad thing" and has urged investors to be more defensive amid fears risky behaviour has led to excesses in private equity and debt.

The co-chairman of US-based fund manager Oaktree Capital cautioned that the reversal of globalisation at a time of simmering trade tensions between the US and China, coupled with growing political populism, could sap global growth over coming years.