The Sun says the Chelsea and England ace, 32, proposed on one knee during a romantic dinner in the U.S. earlier this week.
The couple, who have been dating for 18 months, are on a two-week sunshine break in California.
And this morning The Daybreak presenter called the ITV1 show from Los Angeles to tell of her surprise.
She said: "I was beyond shocked. It wasn't very glamorous, it wasn't very fancy, I know maybe some people might expect that.
"It was very personal, very private, actually. We were just having a gorgeous lunch by the beach and he simply popped the question.
"It was completely out of the blue and he was starting to build up to it and it was a little bit lovey-dovey and halfway through the lovey-dovey bit I realised what he was about to say and I started to cry."
Frank's agent Steve Kuttner added: "I am pleased to say that Christine Bleakley has accepted Frank Lampard's surprise engagement proposal here in Los Angeles.
"They are obviously both delighted but there are no immediate wedding plans, and the couple will not be making any further comment on this happy and private occasion."