The Home Office has detained the first migrants bound for Rwanda, a week after the plan was voted into law.
Operational teams within the Home Office have been "working at pace to safely and swiftly detain individuals" for relocation to Rwanda, the department said.
More detentions are expected to take place in the coming weeks, ahead of flights expected to take off at the begining of July.
Home Secretary James Cleverly said: "Our Rwanda Partnership is a pioneering response to the global challenge of illegal migration, and we have worked tirelessly to introduce new, robust legislation to deliver it.
The Home Office has released footage of the detentions of the first migrants bound for Rwanda
PA
"Our dedicated enforcement teams are working at pace to swiftly detain those who have no right to be here so we can get flights off the ground.
"This is a complex piece of work, but we remain absolutely committed to operationalising the policy, to stop the boats and break the business model of people smuggling gangs.”
Home Office Director of Enforcement Eddy Montgomery added: "Our specialist operational teams are highly trained and fully equipped to carry out the necessary enforcement activity at pace and in the safest way possible.
"It is vital that operational detail is kept to a minimum, to protect colleagues involved and those being detained, as well as ensuring we can deliver this large-scale operation as quickly as possible."
More than 1,000 migrants have arrived on UK shores in small boats in the week since the Rwanda Bill received Royal Assent, despite the Prime Minister saying the legislation would deter migrants from making crossings.
A total of 132 migrants arrived on UK shores on Monday in three boats, taking the total number of arrivals in the previous seven days to 1,032.
Operational teams within the Home Office have been working at pace to "safely and swiftly detain individuals" for relocation to Rwanda, the department said
PA
This takes the total for the year to 7,299 - an increase of exactly 1,500 on the same time last year. This is an increase of 25.9 per cent, and an increase of nine per cent on 2022.
The Government’s Rwanda deportation plan passed through Parliament last week following an extended process of parliamentary ping pong between MPs and Lords.
The unelected chamber ended the deadlock after MPs rejected a requirement that Rwanda could not be treated as safe until the secretary of state, having consulted an independent monitoring body, made a statement to Parliament to that effect.
The Government said the Lords amendment was "almost identical" to the previous ones overturned by MPs.
At the time of its passing, Sunak said the legislation will "deter vulnerable migrants from making perilous crossings".
In a statement, the PM said: "The passing of this landmark legislation is not just a step forward but a fundamental change in the global equation on migration.
"We introduced the Rwanda Bill to deter vulnerable migrants from making perilous crossings and break the business model of the criminal gangs who exploit them.
"The passing of this legislation will allow us to do that and make it very clear that if you come here illegally, you will not be able to stay.