The leaders of seven countries that share the world's second largest tropical forest, pledged a joint effort to protect their common resources.
The members of the Congo Forest Basin Partnership promised to encourage sustainable management of logging concessions, and to increase protection of endangered species, like the forest's unique lowland gorillas.
Host President Denis Sassou Nguesso said he is confident that the countries will move from words to actions, now that a treaty has been agreed upon.
But environmental activists say that may be difficult. Filip Verbelen of the environmental group, Greenpeace, said that, although some progress has been made in recent years, environmental efforts are hampered by corruption. "Let's make that very clear that there are vested interests in maintaining the status quo. People are gaining and making profits from corruption and illegal logging. So, I do think that this pressure will need to be really strong, before we can see some changes on the ground," he said.
Environmentalists warn that illegal logging could destroy as much as two-thirds of the Congo Basin's forest in 50 years. Environmental policies formulated at the first forest summit five years ago have not lived up to expectations, but proponents of the Congo Basin Forest Partnership say this is because they did not receive sufficient Western backing.
French President Jaques Chirac, the only non-African leader to attend, said that the West must be ready to pay some of the costs of preserving a region of vital importance to the planet.
The Congo Forest Basin is home to more than half of Africa's animal species, and is one of the richest ecosystems on the planet.