Stephen McGown of South Africa and Johan Gustafsson of Sweden appeared in "proof of life" video clips apparently produced in October, the Gift of the Givers charity
The two men were believed to be abducted by al Qaeda in the Islamic Maghreb in Mali in 2011.
One video shows McGown wearing a brown collared shirt in front of a brown cloth-covered background.
"My name is Stephen McGown. I'm a South African citizen. Today's date is Tuesday, the 20th of October 2015," he says in the video
"Short message to the South African government: I thank you for your continued efforts in negotiating my release. My wife and my family, I am well. I hope you are all well back home. I understand that I will be seeing you soon."
Gustafsson, also wearing a brown shirt in front of a brown cloth background, gave a similar message.
"I would like to acknowledge any effort or help from my government in my release. I'm safe and sound in good health," the Swedish citizen said
. "I miss my family very much.
Gift of the Givers expressed optimism after watching the footage.
"The most heartening aspect of the video is the fact that the captives are now aware that negotiations are underway for their release, which would certainly instill a great deal of hope and positivity in them," the charity said.
"The road is still long but we will make progress."