In a Facebook post, he was raising concerns over Trump’s travel ban on immigrants.
Farah had said: "On 1 January this year, Her Majesty The Queen made me a Knight of the Realm. On 27 January, President Donald Trump seems to have made me an alien."
Somali nationals are among those banned from travelling to the US under the executive order issued last Friday.
That had applied to Farah, who was born in Somalia, until an announcement by the UK Foreign Office late on Sunday had later clarified that the ban did not apply to him.
The Foreign Office then advised British travellers that dual citizens were only affected if travelling to the US from one of the seven banned countries.
In response, a spokesman of Farah had thanked the Foreign office for the clarification and said that the athlete was “relieved that he will be able to return to his family once his current training camp concludes."
However, the statement added that Farah "still fundamentally disagrees with this incredibly divisive and discriminatory policy".