Britain has made payments to Rwanda as part of its £120 million ($147m) asylum scheme despite legal challenges delaying the introduction of the policy.
The Rwandan government has already begun spending the cash, it says, to ensure it was ready for last week’s first flight, which was cancelled at the last minute.
Downing Street conceded some payments had been made to Rwanda, but would not reveal how much or when under the “confidential” deal signed two months ago.
The payments came despite the suspension of one-way flights for migrants who arrive in the UK through unauthorised journeys.
Rwanda government spokeswoman Yolande Makolo said the payments were "intended to prepare for all the accommodations and all the other institutions to, you know, beef up the processes.
"So that’s that’s been done."
Ms Makolo said the government had spent "part of it because we needed to get ready and we were ready to receive the first migrants on the 14th".
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The first flight was halted after an interim injunction from the European Court of Human Rights, pending a decision on the legality of the scheme in the UK courts.
“The agreement with Rwanda with regards to the funding is confidential," said British Prime Minister Boris Johnson's spokesman.
"It’s fair to say we have made some payments as part of that migration partnership, that’s correct."
“Obviously there’s a number of pieces of work they need to do to get things ready, to get things set up.”
Inside a refugee camp in Rwanda - video
Inside a refugee camp in Rwanda
