The 32-year-old actor took charge of his role as the associate director of the White House Office of Public Engagement on Monday.
"This is an incredibly historic time, I am deeply honoured to be here and I hope to serve my country to the best of my ability," Penn told reporters at the White House.
Penn's first day in the capacity of Associate Director in the White House's Office of Public Engagement, mostly involved paper work, introductory meetings and setting up of emails.
Penn, whose real name is Kalpen Modi, had actively campaigned for Barack Obama during his presidential campaign.
The actor, who has worked in a number of Hollywood projects including Meera Nair's critically acclaimed film The Namesake, TV shows Harold and Kumar and Fox medical drama House, intends to actively engage the youth and the Asian American communities in his new role.
When asked about his new job, Penn said, "The job is very different, as you can imagine. I'm wearing a suit ... and a tie."
The actor took a bus to reach the White House for work on his first day. Penn said he is renting a place for his stay in Washington for his new assignment.
Penn described his office as 'front door to the White House'. He told reporters that he expected to be treated just like any other staff member at the White House.
Image: A file photograph of actor Kal Penn at the 'We Are One: Inaugural Celebration' at the Lincoln Memorial in Washington
Photograph: Jason Reed | Reuters
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