In their first joint visit, the two ministers travelled to Maiduguri, the capital of the north-east state of Borno, which suffered the worst killings by the Islamist terrorist group, including attacks at the university campus.
Overall Boko Haram has killed more than 20,000 people, displaced 1.7 million and left 8.5 million in desperate need of urgent support, in some cases on the brink of famine. Borno itself has seen more than 27,000 killings by the terrorist group and others.
Boko Haram is trying to create an Islamic state in the Lake Chad region, which spans parts of Nigeria, Niger, Cameroon and Chad. It gained notoriety by abducting more than 200 girls from the north-east Nigerian town of Chibok in April 2014. Aid groups say it has kidnapped thousands more adults and children.
The UK has so far trained 28,000 Nigerian soldiers and over 40 UK military personnel have been deployed to Nigeria on a long term basis.
On Wednesday, Patel announced an extended five-year package of help, costing an extra £200m, to prevent 1.5 million people lapsing into famine and help keep a 100,000 boys and girls in education. The development secretary’s package also includes the restoration of key infrastructure and services in the north-east of the country.
Johnson said: “Boko Haram has generated suffering, instability and poverty on a huge scale, with profound knock-on effects far from Nigeria’s borders.”
He met survivors of Boko Haram violence, including bomb and gunshot victims, and saw for himself the displacement of people created by the conflict.
Johnson, under criticism at home for his performance as foreign secretary, said he was proud of the help the UK was providing: “This is about helping a Commonwealth partner in its time of need as well as addressing the root causes of international challenges such as migration.”
Patel said: “It is catastrophic that at least 20,000 people have been murdered by Boko Haram’s terrorist regime, and over 5 million people have been left hungry and many homeless. Babies’ bodies are shutting down and mothers who have lost everything are fighting to keep their children alive.”
Boko Haram has responded to its loss of territory by resorting to guerrilla tactics on soft targets such as markets, often using children as suicide bombers. Unicef claims the number of child suicide bombers in 2017 has reached 83 this year; more than four times the figure in 2016.
Nigerian ministers have previously prematurely claimed the terrorist group had been suppressed.
At the weekend it was confirmed that the US was selling Nigeria surveillance aircraft that will make the fight against terrorism much more effective. The weapons sale, consisting of $593m worth of equipment including 12 Super Tucano A-29 surveillance and attack planes, was initially signed off under former US president Barack Obama. However, it was delayed over concerns about alleged human rights violations by Nigerian troops.
Those concerns stemmed from report by rights group Amnesty International in March 2015, which claimed that Nigeria’s military arbitrarily detained and killed civilians in the north-east.
The visit by the UK ministers coincided with the first cabinet meeting overseen by Nigerian prime minister Muhammadu Buhari since his much-criticised 104 days spent in the UK for health treatment.
The country, rich in oil reserves, remains wracked by corruption, with more than $20m recently seized by authorities from the bank account of the former oil minister, Diezani Alison-Madueke. It is alledged that she has gone into hiding after travelling to London.