buhari
President of Nigeria Muhammadu Buhari speaks at the U.S.-Africa Business Forum at the Plaza Hotel, Sept. 21, 2016, in New York City. Drew Angerer/Getty Images

Nigerian President Muhammadu Buhari has decided to stay in London a bit longer than expected amid his vacation to London for what has only been described as medical reasons. An aide for the president made the announcement Sunday night, according to the Premium Times of Nigeria.

Buhari told the National Assembly “of his desire to extend his leave in order to complete and receive the results of a series of tests recommended by his doctors,” Femi Adesina said.

But without having disclosed to his constituents the nature of those medical reasons, rumors of his death or eventual demise from deteriorating health have circulated for weeks since Buhari announced his vacation late last month.

In making the initial announcement to travel to London Jan. 23 and return Monday, Buhari temporarily transferred presidential power to his Vice President Yemi Osinbajo, something that has likely heightened speculation about the president's health after announcing his extended stay abroad.

The speculation went so far as to turn to rumors of Buhari's death last month. Nigerians living in the U.K. have decried those rumors and blamed them on wishful thinking by people who oppose Buhari's politics, according to Vanguard NGR.

"The irresponsible news could only have been floated by those that want to see Nigeria go up in flames. Unfortunately, they failed to realize that the change and reforms initiated by Mr President would outlive everyone since they are targeted at strengthening institutions and building systems," said Adekaa Onyilo, of the UK chapter of Nigerians in Diaspora Monitoring Group. "We therefore want to warn the purveyors of such rumors to desist as their act affect more than President Buhari. At a time when our dear country is working to contain the pressure on the naira, their action has served to further spook the currency and shake investors’ confidence. When this happens, citizens that played no role in starting the lies would suffer for it."

Buhari was also in London over the summer for an ear infection, local news outlet NAIJ reported last June. However, a chronic cough by the president prompted British doctors treating him to x-ray Buhari's chest.