Canada is consulting its allies in the West and working diplomatically with its friends in Africa, Harper said Tuesday.
"Obviously we are very concerned about the situation. The development of essentially an entire terrorist region in the middle of Africa is obviously of great concern to everyone in the international community," he said.
Harper was meeting with Thomas Boni Yayi, president of the Republic of Benin and chairman of the African Union, who said he wants to see NATO add its forces to the African forces tasked with dealing with Mali.
"There are also other forces outside the African continent that could contribute to take into account the seriousness of the situation and the resources that are required to implement this," Boni Yayi said.
"We need to react for the simple reason that this issue goes well beyond the scope of Africa, but also we must focus on the fact that the scourge of terrorism is an issue of the entire international community."
Mali was struck by a military coup last March and now has a group linked to al-Qaeda controlling its north.
The UN Security Council backed a proposal in December to send an African-led force of 3,300 soldiers into the country, but the resolution also called for broader international assistance.
Funding, investment agreement
Harper and Boni Yayi announced they have signed a foreign investment protection agreement, which Harper's office says locks in legally binding provisions, such as on non-discrimination and free movement of capital.
Harper also announced $18 million from 2013 to 2021 to help Benin improve its tax collection and policy implementation.
"We need internal revenue collection in order to have more independence," Boni Yayi said.
Asked what Canada will do to alleviate poverty in Benin, Harper pointed to the work on tax collection and investment.
"For the creation of growth in any country, it's really the government of that country that has to lead that vision," he said.
Harper also pointed to the African Union's mining sector initiative, "which is really essential if Africa is not only going to exploit its resources but do so in a way that is ultimately of benefit to all the people that live in Africa."
Boni Yayi referred back to 2009 when Benin was cut from Canada's list of focus countries, in which aid money is concentrated, and asked to be returned to it.
"For reasons specific to our privileged partner here, Benin was removed from countries of focus, but even the countries of focus have not benefited as much from Canada's care and concern as we have," he said."It's time to call a spade a spade. Since we continue to benefit from the attention of Canada, it's time that Benin returns to the list of countries of focus."