US Secretary of State Hillary Clinton arrived in Senegal's capital Dakar at the start of a seven-nation, 11-day trip to Africa due to focus on regional peace and security.
The top diplomat, whose tour will take her to the world's newest nation, South Sudan, as well as Ebola-hit Uganda, was expected to meet Senegalese President Macky Sall Wednesday.
Sall's coalition won a landslide majority in legislative polls earlier this month, securing 119 of 150 seats in the national assembly.
"Our desire is to applaud the election of President Sall," a US official said. "Senegal has been our strongest and most reliable partner in francophone Africa".
The US foreign affairs chief was also expected to make a speech at Dakar's Cheikh Anta Diop University.
Clinton will "deliver a speech applauding the resilience of Senegal's democratic institutions and highlighting America's approach to partnership," State Department spokeswoman Victoria Nuland said in a statement.
Clinton is then expected to head on to South Sudan, followed by stops in Uganda, Kenya, Malawi, South Africa and Ghana.
Clinton was originally only expected to visit six nations but will now also stop in Ghana to attend the August 10 state funeral of president John Atta Milla who died on July 24, according to a US official.
In June, US President Barack Obama had laid out his strategy for African development with the aim of consolidating security and democracy and stimulating growth on a continent faced with threats from Al-Qaeda and a Chinese economic offensive.
"We want to underscore the US importance for strong, open, accountable and democratic institutions," the US official said. "We want to expand opportunities for US trade and development. Our desire is to encourage better growth and investment."
A likely highlight of the trip will be a meeting with 94-year-old former South African president and democracy icon, Nelson Mandela.
Clinton's trip comes only two weeks after a tour to Europe, Asia and the Middle East, during which she visited Laos and Mongolia, bringing her tally for nations visited as secretary of state to a record-breaking 102.
Her trip to Juba, the capital of South Sudan, will expand that list even further.
South Sudan broke away from Sudan in July last year but the two have yet to set a definitive border and are in dispute over oil revenues and citizenship rules.
The United States is leading international calls to the two neighbors to step up efforts to reach a peace deal this week or face possible United Nations sanctions.
The UN Security Council has given the two states, who this year came close to all-out war, until Thursday to make a peace deal.
While in South Sudan, Clinton will meet President Salva Kiir "to reaffirm US support and to encourage progress in negotiations with Sudan to reach agreement on issues related to security, oil and citizenship," Nuland said.
Before returning to the United States on August 10, Clinton will also stop in Uganda, undeterred by reports that the deadly Ebola virus has reached the capital Kampala.
Fourteen people have died since Ebola broke out in western Uganda three weeks ago.
In Kenya, Clinton will hold talks with top officials, and, "to underscore US support for completing the political transition in Somalia by August 20," will also meet Somali President Sharif Sheikh Ahmed, according to Nuland.
After visiting Malawi, Clinton will head to South Africa accompanied by an American business delegation.