Serena Alexander-Benson was last seen by her father leaving their home address in Wimbledon just before 8am on 25 May.
She had told her father she was going to school and the alarm was raised after she failed to arrive.
Police investigations found out she left the UK via the Eurotunnel in Folkstone with an older woman the same day.
It later emerged she was travelling in a car with a female friend of her mother.
The National Crime Agency has since been in contact with Polish authorities who have confirmed Serena is with her mother in Poland.
A Met Police statement said: “Enquires continue to establish whether any offences have been committed.
“There has been no European Arrest Warrant issued.”
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It is understood her mother lives in Poland.
Police previously said their priority was ensuring Serena was safe, after which point they would consider potential charges.