Please provide evidence
“Long long ago, in the champakavaTI forest of magadha, there lived two friends – a Deer called chitrA~Nga and a Crow named subuddhi. It so happened that a Jackal named kshudra-buddhi, (the proposer of vasudhaiva kuTumbakam, as we shall soon see), was passing by and his eyes caught hold of the healthy Deer as he was grazing nearby. The lust to devour him immediately arose in the Jackal’s mind, but knowing Deer to be too swift in a chase, he decided to fall back on his cunning – to win first the confidence of the Deer. The VK-preacher therefore approached the Deer, saluted him, and introduced himself as a lonely newcomer with friendly intentions, and proposed a friendship and brotherhood with the Deer. The naive Deer fell for the sweet words of kshudra-buddhi, and not knowing his true intentions, invited him to his own dwellings.So, they started towards the Deer’s place, and on their way sitting on the branches of a champaka tree was Deer’s old and wise friend subuddhi the Crow. Seeing them passing by, the Crow asked the Deer, ‘O chitrA~Nga, who is this second fellow with you? ‘ ‘A Jackal, my new friend’, answered the Deer. To this, the Crow asked: ‘But, do you know him well enough? One should never extend friendship and shelter to anyone without knowing their real nature and intentions, learning the history of their ilk and giving them a test of time.’ The Deer lightly shrugged this aside, saying, ‘But this Jackal is very friendly’.Seeing his friend in delusions, the Crow began relating to him a story about how jaradgava a Vulture was killed by unwisely trusting an impostor (that story reproduced later below). He warned the Deer against trusting the Jackal without learning more about him.So far the Jackal had kept quiet, and it is at this juncture that he opened his argument with the famous shloka of vasudhaiva kuTumbakam, demanding the Deer to not be of a narrow mind by considering the Crow a friend and himself an alien. The vasudhaiva-kuTumbakam discourse successfully put to rest all doubts that had arisen in the Deer’s mind, and dismissing the Crow’s wise council he went ahead in bringing the VK-preacher into his home.”
There is a prohibition from Brahmins leaving the confines of Bharatavarsha but certainly not Kshatriyas invading foreign regions.
Please provide the verse and context.