RIYADH - Saudi Arabia on Monday sacked its veteran finance minister as the kingdom undergoes a major economic restructuring because of lower oil revenues.

Ibrahim al-Assaf "has been removed from his position", said a royal decree, one of a series of orders from King Salman, published by the official SPA news agency.

Assaf was replaced by Mohammed Aljadaan, head of the Capital Market Authority which regulates the stock market.

A foreign diplomat had told AFP weeks ago there was talk of changing the finance minister , who is 67 years old and had held the post for 20 years. Assaf, who has a doctorate in economics, was reassigned as a minister of state and will remain in cabinet. Aljadaan, a lawyer, had led the Capital Market Authority since January last year.

No replacement for him at the market regulator was immediately named.

Since 2014, global oil prices have collapsed by about half, accelerating Saudi efforts to move away from petroleum which still accounts for the bulk of government income. The world's biggest oil exporter is projecting a budget deficit of $87 billion this year.

It has taken a series of austerity measures, including subsidy cuts, reductions in cabinet ministers' salaries and delays in major projects.

Earlier this year, Deputy Crown Prince Mohammed bin Salman, 31, who heads the main economic coordinating body, announced a wide-ranging plan to move the economy away from oil.

Assaf last week said Saudi Arabia's financial position remains strong despite sinking oil prices, although there is "some pressure" on bank liquidity. "We have been able to maintain a good position in public finances," Assaf said. Among measures to cover the fiscal gap, Riyadh has drawn on its foreign reserves and issued domestic bonds before Assaf, two weeks ago, supervised the kingdom's first international bond offering. It raised $17.5b, reflecting strong global interest. Official figures show the kingdom's reserves declined to $562 billion in August from $732b at the end of 2014.

Minister hails 'bold' deal with Japan's SoftBank

The Saudi energy minister said Tuesday that a multi-billion-dollar technology investment fund the kingdom is developing in partnership with Japan's SoftBank showed its determination to diversify its economy.

Khaled al-Falih told an international forum that the proposed new fund "is simply one indication of this determination and the bold steps being taken" to reorient the economy of the world's biggest oil exporter.

Since 2014, global oil prices have collapsed by about half, accelerating Saudi efforts to move away from petroleum, which still accounts for the bulk of government income.

Falih told the KAPSARC Energy Dialogue that in the past the kingdom had not implemented diversification policies "as efficiently as we should have".

Vision 2030 -- a wide-ranging plan released in April -- was a "proactive response" to build a diversified economy led by the private sector and with international investments providing alternative revenue sources, he said.

At the heart of the Vision is a plan to float less than five percent of the state oil company, Saudi Aramco, on the stock market to help create the world's biggest state investment fund.

Under the non-binding agreement reached with SoftBank in October, the kingdom's contribution to the new fund could reach $45 billion.

SoftBank said it hoped to raise up to $100 billion for the fund designed to invest in promising technology firms.

Although Saudi Arabia wants to seize opportunities in a world that will be increasingly technology intensive, Falih said the kingdom would not reduce the contribution of its traditional pillars of oil and gas, petrochemicals and mining.

It will rather be "enhancing the development of other industrial and economic sectors to rebalance and accelerate the growth of the overall economy".

The kingdom projects a budget deficit of $87 billion this year.

It has taken a series of austerity measures, including subsidy cuts, salary reductions and delays in major projects.

Two weeks ago, the kingdom's first international bond issue raised $17.5 billion.

On Monday night King Salman, 80, sacked veteran Finance Minister Ibrahim al-Assaf, 67, who supervised the successful bond offering.

He is the latest long-serving minister replaced in a government where Salman's son, Deputy Crown Prince Mohammed bin Salman, 31, wields unusual power and symbolises the potential of youth in a kingdom where more than half of Saudi citizens are aged under 25.

London-based analysts at Capital Economics said they do not think Assaf's dismissal signals a change in the government's approach to lower oil prices.

"The new finance minister , Mohammed Aljadaan, is generally considered to be a reformer within the government and a close ally" of Prince Mohammed, Capital Economics said.

Aljadaan headed the kingdom's stock market regulator and supervised the bourse's opening last year to foreign investors.