An Iranian Revolutionary Guards commander says US bases and aircraft carriers are within range of Iranian missiles.

"Everybody should know that all American bases and their aircraft carriers in a distance of up to 2000 kilometres around Iran are within the range of our missiles," said the head of Iran's Revolutionary Guards Corps Aerospace Force Amirali Hajizadeh.

The semi-official Tasnim news agency also quoted him saying that "Iran has always been ready for a 'full-fledged' war."

Hajizadeh's chilling remarks came a day after Yemen's Iran-aligned Houthi group attacked two Saudi Aramco oil plants. The drone strikes reportedly took out half the kingdom's output, which works out to 5 percent of the world's oil supply.

The pre-dawn attack on the facilities sparked several fires although the kingdom, the world's largest oil exporter, later said these were brought under control.

The attacks occurred as Aramco accelerates plans for an initial public offering of the state oil giant to as early as this year, and follow earlier cross-border attacks on Saudi oil installations and on oil tankers in Gulf waters. Saturday's attacks appeared to be the most brazen yet.

Crown Prince Mohammed bin Salman told US President Donald Trump in a phone call that Saudi Arabia is "willing and able" to respond to the attacks, according to the official Saudi Press Agency.

Trump replied that the US is ready to co-operate with the kingdom on security.