Speaking on LTV's morning news show Rita Panorama, Rasnačs said he "both supported and did not support" Biden's claim that an opaque and slow court system, plus suspicions of corruption, were putting a brake on foreign investment.
"We have very carefully examined what is written on the White House home page and have to say this information is a little out of date... since May there have been some changes," Rasnačs said.
Probably officials including himself had not been active enough in communicating recent improvements to foreign ambassadors, Rasnačs added, saying he would now make a concerted effort to do so.
Then in a move suggesting that the minister had prepared an answer to the question far in advance of his appearance on the show, he picked up two graphics he had to hand based on Latvian central bank figures and held them up to the cameras, which obligingly zoomed in to show graphs indicating that investment from the USA was increasing.
Rasnačs then repeated the trick with a graph showing investment from EU countries.
Asked if Biden was not well enough informed, Rasnačs replied: "I think he's well informed, but that information is out of date," and underlined that investment from both the US and EU was growing.
During his recent visit to Latvia, VP Biden said one of the key barriers to US companies investing more in Latvia was a lack of faith in the legal system which he singled out for criticism in a speech otherwise effusive in its praise of the Baltic states.
"In democracy, it’s a civic duty to ensure governments are accountable to their citizens and not the narrow interests of the powerful," Biden said.
"The rule of law has to apply equally to everyone. Justice systems must be equitable and efficient and transparent. Otherwise, we will not attract international commerce and business.
"And in a moment when Russia seeks to use corruption as a tool of coercion and influence around the globe, rooting out corruption is essential to preserve your national sovereignty. It’s a cancer to the body politic. It’s among the highest acts of patriotism to root it out," Biden said.