Zoe Saldana's husband has become a US citizen.

(c) Zoe Saldana/Instagram

(c) Zoe Saldana/Instagram

The 'Nina' actress shared a picture of Italian-born artist Marco Perego driving to receive his US citizenship and encouraged others to persevere if they are having trouble obtaining it, insisting the couple - who have 20-month-old sons Cy and Bowie - are sending "good vibes".

She wrote: "On our way to be sworn in as a US Citizen. Marco has been dreaming about this moment for a long time. It was a process- as it should be, but we are finally here. We are aware it isn't as easy for many immigrants to obtain their citizenship, we say to them NEVER GIVE UP. Stay the course, America would not be what it is if not for the immigrants that come for better opportunities. We send love and good vibes to you all today. #newuscitizen (sic)"

The 38-year-old star also shared a picture of Marco and her mother, who once had to get her citizenship, and in the background was 'Selma' star David Oyelowo and his wife Jessica who were getting their naturalisation.

She added the caption: "My mom has been a citizen since she was a young girl. Her mother arrived in NYC in 1961 and brought my mother from Dominican Republic when she was 10. My sisters and I are indebted to them both. Because of them we are American women. So proud she is here supporting Marco! Oh check out who is getting their naturalization today too... David Oyelowo and his Wife!!!!! Congrats! #newuscitizen (sic)"

Zoe and Marco began dating in March 2013 and tied the knot just three months later in London.