The Austrian left his third driver role at Honda to go in search of a race seat for 2008 and was one of seven drivers to take part in a shootout for the second Force India seat.
However despite setting some impressive lap times, he lost out to Fisichella for the drive while his old friend Liuzzi was named the teams test and reserve driver.
Klien thanked the team for the opportunity of the two tests before Christmas.
"I would like to thank Force India F1 for providing me with the testing opportunities in Barcelona and Jerez," he said in a statement on his website
"It was a very satisfying experience and the team did a really good job.
"I was happy to be fastest in Jerez and feel I worked very well with the team.
"There was intense competition for the remaining race seat beside Adrian Sutil and that was my goal after a season as test and reserve driver for the Honda Racing F1 Team.”
Klien had initially hoped that his year in a test role at Honda would revive his F1 race career after splitting with long-time backers Red Bull in 2006, but the Brackley squad opted to retain its current driver line-up.
He says he hasnt given up on a return to the sport in future, but admits he now must ensure he lands a race role in another series.
"Obviously my first choice remains Formula 1,” he said.
“It is important to me, however, to keep my race skills fully exercised.
“Therefore, I have been considering other options for the 2008 season.
"There are good opportunities outside of Formula 1, that I want to explore and I am very much looking forward to developments in the coming weeks."