President-elect Donald Trump has confirmed the chief executive of Exxon Mobil, Rex Tillerson, as his choice for U.S. secretary of state, BBC News reports.

In a statement, Trump praised Tillerson, 64, as among the "most accomplished business leaders and international dealmakers" in the world.

Tillerson is said to have a good relationship with Russian President Vladimir Putin, alarming both Democrats and some Republicans.

The nomination needs Senate approval.

Days ago it emerged that U.S. intelligence agencies believe Russia acted covertly to boost Donald Trump in the election race.

The secretary of state is in effect the most senior U.S. diplomat, responsible for enacting the government's foreign policy.

Under a Trump presidency, his in-tray could include everything from handling rows with China to revisiting the nuclear accord with Iran.