Felix Tshisekedi has said national reconciliation is a priority in his presidency, reports our correspondent Gaius Kowene. The remark was in the final part of his speech that was in danger, at one point, of not being delivered.
The new president returned to the stage in the capital, Kinshasa, to finish his inauguration speech after falling ill part-way through.
He also promised to change the electoral law in the country where his own election win has been contested by the opposition.