Two days after President Barack Obama announced that he wanted to cut defense spending by $400 billion over the next decade, the Pentagon is reporting that the price tag for its most expensive weapons programs will be going up – by $64 billion.

Defense Secretary Robert Gates. (AP Photo/Chip Somodevilla, Pool)

On Friday, the Department of Defense sent Congress its latest “selected acquisition reports,” a list that outlines long-term cost estimates for nearly 100 weapons-buying programs. According to the report, which is based on data from the end of 2010, those weapons accounts – a potential total of $1.6 trillion — saw a net increase of 4% over the previous reporting year.

That doesn’t necessarily mean it will be harder to meet the president’s goal of scaling back defense outlays by 2023. The reports project out the cost of buying some weapons over several decades, and represent the department’s best estimate of the total “life cycle” cost of ships, fighters and missiles that may still be in service in 2030 or 2040…