Tillerson flew to Nigeria after Chad for a stay of just a few hours, less than the overnight visit originally planned.
Washington's top diplomat has been on a five-country tour of east and west Africa but was forced to cut short his visit "due to demands in (his) schedule", the State Department said.
Receiving the American Secretary of State, Rex Tillerson, in an audience at State House, Abuja, Monday, President Buhari added that Nigeria was working in concert with worldwide organizations and negotiators, to ensure that the girls were released unharmed by their captors.
U.S. secretary of state Rex Tillerson will cut short his first diplomatic trip to Africa on Monday to return to deal with urgent work in Washington, his spokesman said.
Secretary of State Rex Tillerson is ending his first diplomatic trip early and flying back to Washington Monday because of new developments in the administration's approach to North Korea.
"Tillerson's travel plans have changed so that he can return to Washington early on Tuesday morning instead of late that night", a spokesman for the top US diplomat told reporters in Nairobi Kenya.
The Secretary expressed concern about the recent attacks and abductions and agreed to expand counterterrorism cooperation to diminish the threats to USA and Nigerian interests.
Tillerson visited N'Djamena, Chad's capital, on what was later announced to be the last day of his African visit.
On Saturday while visiting Nairobi, Tillerson, cancelled his scheduled events because he had been feeling unwell.
After his meeting with President, Mr. Tillerson is now holding a press conference with his Nigerian counterpart, Geoffrey Onyeama.
According to him, the USA government will also offer special training for security personnel to enable them engage in special operations towards the rescue of the girls abducted by the Boko Haram terrorists.