Dutch defense ministry officials also met political party representatives last week to run through the various problems.
“Politicians are worried, but not overly worried,” about the cost overruns, delays and technical problems, the source said.
Senior Dutch officials participated in a regular twice-yearly all-day meeting of the United States and all the partners helping fund the F-35’s development in Washington on Wednesday.
U.S. defense sources said the meeting included discussions about the start of operational testing of the new jet, an issue of concern to the Netherlands, which has ordered two planes with extensive sensors and wiring to participate in test flights.
U.S. defense officials say the Netherlands remains active in the program and has not reduced its projected orders.
Some Dutch politicians question whether the country needs such an expensive fighter, or whether to go for an alternative such as Saab AB’s Gripen, Boeing Co’s F/A-18 E/F Super Hornet, or the EADS Eurofighter.
Lockheed officials insist the plane’s production costs are coming down and say none of those other airplanes would give the Netherlands the same fifth-generation capabilities of the F-35.
“The Dutch have to make up their minds about what they want their military’s role to be. If they want to participate in coalitions in the future, they’ll stick with the F-35,” said one source familiar with the F-35 program.