Base metals prices on the London Metal Exchange closed lower across the board on Tuesday March 20, with copper falling to a new 2018 low. Read more in our live futures report.

Here are how LME prices looked at Tuesday's close:

Comex copper prices tumbled to the lowest level since mid-December after investors moved to the sidelines ahead of a critical central bank meeting in the United States.

The European ferro-chrome benchmark is expected to rise sharply for the second quarter once it is announced later this week, market participants told Metal Bulletin.

Canadian junior miner Wealth Minerals has entered an agreement with Chile’s state-owned Empresa Nacional de Mineria to help it develop and commercialize its lithium projects in Salar de Atacama in the country's north and Laguna Verde in the Valparaíso Region.

The main union at Antofagasta's Los Pelambres copper mine in Chile has agreed to extend government-led mediation by five days, postponing a potential strike there.

In the steel market, German government figures and steel companies are looking for a quick resolution to concerns created by the impending US tariffs on imports of European steel.

Moreover, European steel association Eurofer has called on the region’s political leaders “to stand united in backing a broad, firm and decisive response [to the US import tariffs] to safeguard the viability of the EU steel industry.”

US steelmaker Big River Steel will soon decide whether to double its production capacity in its efforts to become a go-to supplier for the electric vehicle market, a company executive said.