The UK-led JEF will consist of troops from nine NATO members and partner countries.
"It means 10,000 troops from nine countries today are already prepared for deployment at any time if unexpected crisis situations arise," Karoblis wrote on Facebook. "The agreement marks the end of the JEF creation and its complete readiness."
According to the Ministry of National Defense, the JEF will follow NATO standards and procedures and be able to bolster other international high readiness forces and support UN, NATO and EU actions.
"This force is another deterrence and defense measure. It’s also a measure for increasing security for Lithuania and the whole region and strengthening European military capabilities. Such rapid response units are very much needed in today's security situation. Moreover, it's a great opportunity for Lithuanian troops to improve their skills working with UK troops," the Lithuanian defense minister said.
A letter of intern on the creation of the UK Joint Expeditionary Force was signed by then Lithuanian National Defense Minister Juozas Olekas in 2014.
During his visit to London, Karoblis is also scheduled to meet with his British counterpart Gavin Alexander Williamson and discuss the upcoming NATO summit, bilateral cooperation and new initiatives.