A Catholic bishop in Nigeria has criticised the government, likening it to the terrorist group Boko Haram, for not doing enough after the Christmas murders of Christians.

Bishop Matthew Hassan Kukah of Sokoto told Catholic charity Aid to the Church in Need he was disgusted with the authorities after the beheading of ten Christians by Islamic State in Borno state, released in a video on Boxing Day.

President Muhammadu Buhari condemned the murders on Twitter and said the murderers had given Islam a bad name.

President Buhari wrote: "These agents of darkness are enemies of our common humanity and they don't spare any victim, whether they are Muslims or Christians, and therefore, we shouldn't let them divide us and turn us against one another."

We should under no circumstances let the terrorists divide us by turning Christians against Muslims, because these barbaric killers do not represent Islam and millions of other law-abiding Muslims around the world. — Muhammadu Buhari (@MBuhari) December 27, 2019

Bishop Kukah of Sokoto, a city in the north west, criticised Buhari's government, saying: "The only difference between the government and Boko Haram is Boko Haram is holding a bomb.

"They are using the levers of power to secure the supremacy of Islam, which then gives more weight to the idea that it can be achieved by violence. With the situation in Nigeria, it is hard to see the moral basis they have to defeat Boko Haram.

"They have created the conditions to make it possible for Boko Haram to behave the way they are behaving."

The murderers said they were avenging the death of Abu Bakr al-Baghadi, Daesh (ISIS)'s leader, and other senior Daesh members killed during a US raid in October.

This attack followed one on Christmas Eve by Boko Haram in which seven were killed.

The UN estimates that over 2.2 million have been displaced by Boko Haram's actions and it's estimated that between 2013 and 2015 more than 11,000 people were killed by the group.

Bishop Kukah said the Nigerian government gives tacit approval to such groups.

"If the people in power don't do enough to integrate Christians then they give oxygen to Islamism. If they have countries where everybody is Muslim in power then you give vent to the idea that Islam should be supreme."

He added that the country is not receiving help from abroad: "Western nations are not doing enough. They have shown that the resources of Africa are more important than the ordinary people. Clearly, the Western nations could have reduced the influence of Boko Haram by 80 or 90 percent - they have deliberately not done enough."

The bishop said Christians feel ignored and that it is hard to know how to respond: "Christians have every reason to feel insecure and also there is a general feeling of their marginalisation from the political process. If the principles of our religion were different, there would be a civil war by now.

"It is the glory of our religion that this hasn't happened. It is difficult to preach peace in this context. Any resolution depends on how Christians decide to react. They won't use violence but what will they do?"

