WASHINGTON — Lockheed Martin continues to invest in its portable nuclear fusion generator, with that investment recently entering a more advanced stage, according to the head of the company's Skunk Works division.

Rob Weiss told an audience at the Atlantic Council that Lockheed is "about four months into a little bit more significant investment" into the technology, which was first revealed around two years ago.

At the time of the initial announcement, Lockheed said it was aiming for a 100 megawatt device which could fit on the back of a large truck. Such a reactor, the company claims, could power a city of up to 100,000 people.

Such a technology would be a revolutionary one for an ever energy-dependent country, but would also potentially have major military applications. If the system could be further shrunk, it could potentially become a powerplant for fighter jets, providing the power needed for directed energy weapons and advanced sensors. It could also help power travel for spacecraft.

"This is a great example of one of our creative engineers who was very focused on solving this obviously critical national security level issue, and we are, again, making the appropriate amount of investment today," Weiss said. "It's basically at this stage we are increasing the temperature at which the fusion could occur, and our process for containing the reaction, and we will continue to elevate the level of the temperature and testing the containment theory."

Weiss also confirmed the team has achieved "initial plasma," an important early step for the reactor.

Twitter: @AaronMehta