Buhari joins world leaders one planet summit
I think there may be a mistake here. There is no such event as the "One Planet Summit". However, there is a annual event called the One Planet Summit, which is a global event that brings together world leaders, experts, and stakeholders to discuss and address the challenges of climate change and sustainable development.
The One Planet Summit was first held in 2017, and it is organized by the French government, the United Nations, and the World Bank. The summit aims to mobilize global action to address climate change, promote sustainable development, and achieve the United Nations' Sustainable Development Goals (SDGs).
As for President Muhammadu Buhari of Nigeria, I couldn't find any information on him attending the One Planet Summit. However, Nigeria has been actively participating in international efforts to address climate change and has set its own targets to reduce greenhouse gas emissions and promote sustainable development.
If you have any further information or context about the event you're referring to, I'd be happy to help clarify!