Baby No.2 on the way for Ben Affleck and Jennifer Garner

Garner's former Alias co-star Victor Garber, a close friend of the couple who officiated at their Caribbean wedding in 2005, confirmed the happy news to American magazine Us Weekly.

When asked if the 36-year-old actress was pregnant, Garber said: 'Yes, she is.'

Mummy-to-be: Jennifer Garner, with a loose top concealing her rumoured baby bump, leaves a friend's house in Los Angeles yesterday

The Juno star is rumoured to be five months pregnant with a sibling for their two-year-old daughter Violet.

Speaking of her wish to have another child in October, Garner gushed: 'We definitely wonder what it would be like to have another - hopefully, knock on wood, someday.

'My job is great to have as a mom. I get to take breaks and then work in a really concentrated way. During that concentrated time, it sucks, but whatever.'

Garner and Affleck started dating in July 2004 after splitting from Alias co-star Michael Vartan and Jennifer Lopez respectively.

After wedding in the Turks And Caicos in June 2005, their daughter Violet was born in Los Angeles five months later.

Expanding their brood: Jennifer Garner, pictured in 2005 when pregnant with their first child Violet, and husband Ben Affleck at a baseball game in Boston