Arlington, Virginia, March 21 -- Boeing Co. cautioned that regulatory scrutiny and slower output of its 737 Max jetliner following a January mid-air accident will take a toll on its cash flow projections, a measure closely watched by investors.

Cash outflow will reach $4 billion to $4.5 billion in the first quarter, Boeing Chief Financial Officer Brian West told a Bank of America conference in London on Wednesday (March 20).

A plan to reach a $10 billion cash flow target by 2025-26 will also take longer, though he didn't give specifics. For the year, free cash flow will be in the single digit billions of dollars, West said.

"We're not at the moment where we can manage the near term for these financial outcomes because of the work at ha...