Saudi Arabia has withdrawn as much as $70 billion from global asset managers as OPEC’s largest oil producer seeks to plug its budget deficit after crude slumped, according to financial services market intelligence company Insight Discovery.

“Fund managers we’ve spoken to estimate SAMA has pulled out between $50 billion to $70 billion from global asset managers over the past six months,”

Nigel Sillitoe, chief executive officer of the Dubai-based firm, said by telephone Monday. “Saudi Arabia is withdrawing funds because it’s trying to cut its widening deficit and it’s financing the war in Yemen,” he said, declining to name the fund managers.

Saudi Arabia is seeking to stem a decline in its finances after a 50 percent drop in oil during the past 12 months. The Saudi Arabian Monetary Authority’s reserves held in foreign securities have fallen about 10 percent from a peak of $737 billion last August to $661 billion in July, according to data from the central bank.

With income from oil accounting for about 90 percent of revenue, Saudi Arabia’s budget deficit may widen to 20 percent of gross domestic product this year, according to the International Monetary Fund. SAMA also plans to raise between 90 billion riyals ($24 billion) and 100 billion riyals in bonds before the end of the year as it seeks to diversify its $752 billion economy, people familiar with the matter said in August.

Saudi Arabia is leading a military coalition fighting Houthi rebels in Yemen.

Sillitoe said it’s difficult to determine when Saudi Arabia will “be back in the market to give new mandates” to fund managers.