Saudi Aramco has agreed to supply China’s Huajin Chemical Industries Group Corp 12 million barrels of crude oil under an annual deal for 2018, a considerable rise in supply from last year.

Although it’s a only portion of Aramco’s total supplies to China, the annual deal – the second of its kind between Saudi Arabia and the Chinese company – will help the kingdom boost its market share in the world’s largest crude buyer against competition from industry peers like Russia.

Aramco supplied an estimated 6 to 8 million barrels to Huajin last year, according to Reuters.

In May 2017, Aramco signed a preliminary agreement with Norinco to build a refining and petrochemical project in Panjin.

Russia beat Saudi Arabia to be the top oil supplier to China for the second year in a row in 2017.