The global trade-to-GDP ratio will continue to affect demand for shipping in the years to come, one expert has warned.

Chief shipping analyst of the Baltic and International Maritime Council Peter Sand said this is one of the most worrying trends for the global shipping industry and attributed it to slowing globalisation and trade wars.

Indeed, he particularly criticised the US for its protectionist measures and tariff impositions, although Japan and South Korea were also mentioned as being guilty of this.

Mr Sand said these trends are likely to continue to drag trade volumes and freight rates down.

"The raised barriers to trade are here to stay as we enter a new decade, with the shipping industry stuck with the consequences," he added.

Global trade-to-GDP ratio is calculated by dividing the aggregate value of imports and exports over a particular period by the gross domestic product for the same period.

According to the United Nations Conference on Trade and Development, global trade-to-output ratio returned to about 30 per cent in 2018.

Its projections suggest trade-to-GDP ratio will reach 31 per cent in 2020.