The 33-year-old Werder Bremen captain, who has 79 caps, last played for Germany in February 2009 in a 1-0 loss to Norway.
"We face important decisions in the coming weeks and our position is to openly tell the players how we plan things," Loew told the German federation website.
"That is why we travelled to Bremen to have a long discussion with Torsten because we owe it to him. he has been an important part of the team for many years," said Loew.
Frings featured for Germany in the 2002 and 2006 World Cups as well as in the 2004 and 2008 Euro championships.
However, he fell out with the coach after Germany lost the Euro 2008 final to Spain and was temporarily banned alongside captain Michael Ballack over critical comments in the press.
Frings, who was also called up for the World Cup qualifiers against Liechtenstein and Wales in March and April last year but had to pull out due to an injury, said the decision to leave him out of Germany's World Cup plans did not come as a shock.
"This move does not surprise me," said the midfielder.
"I had to expect that, having seen all the signs. I have no other choice but to accept this decision although I am clearly of a different opinion than Joachim Loew."
"I believe I still have the potential to deliver at a World Cup and will prove it in the Bundesliga," the player said on his website.
Loew said he understood Frings's disappointment but added that younger players were now staking their claim for a place.
"This decision did not come easy but in our wider squad there are a number of young players who meet our expectations and are good prospects for the World Cup and beyond," said Loew.
"It's these young players we want to bring forward because we're convinced of their game and we have a responsibility for their further development," said Loew, who on Thursday will name a pool of players for a two-day performance test next week.
