According to the Financial Times, the force's creation will be spearheaded by Britain and involve contributions from Denmark, Latvia, Estonia, Lithuania, Norway, and the Netherlands. Canada is also interested in joining the group, but it's not known what its final decision will be.
Although no formal announcement has been made, British Prime Minister David Cameron is expected to declare its formation at the upcoming NATO summit in Wales on September 4th.
Many specifics have yet to be worked out or announced, but planners are reportedly implementing ways to increase the number of soldiers involved even more if necessary. Air and naval units will be integrated into the group, as well as ground troops led by British commanders.
As noted by the Times, the creation of the force comes as a response to Russia's involvement in the ongoing Ukrainian crisis, with the ultimate goal being to "create a fully functioning, division-sized force for rapid deployment and regular, frequent exercises." NATO has accused Russia of deploying more than 1,000 troops into Ukraine to bolster separatists in the eastern part of the country.
Russia, however, insists that it does not have troops operating inside of Ukraine and has dismissed NATO's assertions.