The 30-year-old French-born marksman - capped 49 times - attracted Leicester manager Sven-Goran Eriksson because of his turn of foot and the Swedish former England manager believes he can play a decisive role in securing the Foxes a place in the play-offs.
"I like pace, especially in strikers and he has pace," Eriksson told BBC Radio.
"His record is very good. We hope he can help us win more games and score more goals."
Kamara has scored 12 times in 59 appearances for Fulham since joining for £6million from West Brom in 2007, five of those coming in his 11 games this term, though that includes a hat-trick in an FA Cup humbling of League One side Peterborough.
However, he has not started for Fulham in two months, and is expected to make his debut on April 2 against Middlesbrough.
Leicester are six points below the play-off places with eight matches remaining.