The funnyman proposed to British actress Blunt in August (09) after a whirlwind 10-month romance.
The couple is currently planning its nuptials and Krasinski had an insight into what to expect when he shot scenes for U.S. TV's The Office, in which his character Jim Halpert weds his pregnant fiancee Pam Beesly, played by Jenna Fischer.
He says, "I have been getting way too emotional. In the dress rehearsal I was giving the speech at the reception and I started crying, thinking this is so hard!"
Krasinski recently admitted both he and Blunt cried tears of happiness when she accepted his marriage proposal, saying: "She did cry. I cried and we cried and then everyone around us was crying. Then, I think people weren’t really sure what was going on, but they were crying because we were crying. But it was great."
The couple has yet to set a date for its wedding.