It comes during the Nigerian president's state visit to the UK - the first by a west African leader in 37 years.
15 hours ago
Becky MortonPolitical reporter
PA Media
The government has agreed a deal with Nigeria to make it easier to remove people with no right to be in the UK.
For the first time, the Nigerian government will recognise UK letters - an identification document issued to individuals without a valid passport - so people will no longer have to wait for emergency travel documents to be issued before they can be returned.
The agreement was struck during President Bola Ahmed Tinubu state visit to the UK.
Prime Minister Sir Keir Starmer hailed the president's visit - the first by a leader of a west African nation in 37 years - as "historic".
On Wednesday, the King hosted a spectacular state banquet at Windsor Castle for the president and first lady, praising the strength of the ties between the two nations.
President Tinubu also met the prime minister at No 10.
A Downing Street spokesperson said the two leaders "committed to deepening their long-term partnership on trade, infrastructure and sustainable growth".
They also agreed to work more closely together on defence and security in response to transnational crime and terrorism, the spokesperson said.
The Home Office said the immigration deal would make it easier to return people who overstay their visas, foreign criminals and failed asylum seekers.
It said annual returns to Nigeria had nearly doubled to 1,150.
The two countries have also agreed to launch joint operations and share information to crack down on criminal gangs abusing visa routes.
A new standardised document-checking system will be introduced to verify the authenticity of applications.
The Home Office said it followed a series of high-profile cases involving fake job sponsorships, sham marriages and forged financial or employment records.
Meanwhile, Nigeria will review its laws to ensure the toughest possible sentences are given to immigration offenders.
Border Security and Asylum Minister Alex Norris said: "Nigeria is a key partner in our work to tackle illegal migration, as the UK's largest African visa market and home to thousands of Nigerians who have built their lives here."
A separate deal, worth £746m, will see two major ports in Lagos refurbished with the help of UK-backed loans.
UK Export Finance (UKEF), the UK government's export credit agency, has provided a guarantee to the banks loaning the funds under the condition at least 20% of the contracts are sourced from the UK.
At least £236m of supplier contracts will be directed to British firms, including £70m for British steel - the company's largest ever export backed by UKEF.
PA Media
PA Media
Tinubu's visit was also the first to the UK by a Muslim leader during Ramadan in almost a century.
Special adaptations were made to the state banquet, with a prayer room set aside in Windsor Castle, while the usual lunch hosted by the King did not take place as Tinubu was fasting.
On Thursday, First Lady Oluremi Tinubu, who is Christian, also visited Lambeth Palace, the London home of the archbishop of Canterbury.
The visit comes at a time of tension within Nigeria, with a series of suspected suicide bombings this week in the north-eastern state of Borno, in which at least 23 people were killed and 108 injured in attacks blamed on hard-line Islamist militants from the Boko Haram group.
Some 26 million people are "facing extreme hunger" in Kenya, Ethiopia and Somalia, warns humanitarian organisation Oxfam.
Aid groups and MPs have raised concerns over the move to prioritise defence spending over aid.
Caf executive committee member Augustin Senghor says the decision to strip Senegal of the 2025 Afcon title is "unacceptable, abject and we have to denounce it".
President Idris Mahamat Déby orders the military to be on high alert and a "total closure" of the border.