NEW YORK (AP) – The timing of Britain's Royal engagement announcement couldn't have worked out much better for NBC News.

The network had announced, back in April, that it would air a documentary on Prince Charles' environmental work. Accompanied by an interview of Charles by anchor Brian Williams, the two-hour block of programming was scheduled to air tomorrow.

Although Williams had no advanced warning that Charles' son, Prince William, and girlfriend Kate Middleton would announce their engagement on Tuesday, he did think to ask Charles about what advice he'd offer his son about the prospect of a Royal wedding.

NBC and other networks rushed to cover the engagement of two Royals that some in the news business suggested may hold greater fascination for Americans than they do for their countrymen.

In addition to tomorrow's programming, NBC quickly scheduled a prime-time hour for last night, 'William & Kate: A Royal Love Story'. ABC rushed a special edition of 'Nightline' about the engagement on Tuesday. CBS News sent Erica Hill to co-anchor 'The Early Show' from outside Buckingham Palace yesterday.

"I grew up in a New Jersey household with my mom's commemorative Charles & Diana Royal Wedding coffee mug on our kitchen windowsill," Williams said. "I think that describes a lot of households in this country."

'Nightline' had an advantage of an executive producer who hails from Britain, James Goldston, who has been in the United States working for ABC News for five years. He's constantly asked about the Royal family when he meets people in the US, enough to make him think there will be as much or more interest in the wedding here than back home.

The wedding sometime next year has the makings of a huge television event, Goldston said.

"People are very much in the mood for a little escapism right now and there's nothing more fun than princes and princesses," he said.

Rumours that the engagement would be happening soon gave 'Nightline' a head start in preparing for Tuesday's special. The show was built around a long report on the romance that reporter Nick Watt has been working on for several weeks. For news organisations, it is like a happier version of obit preparation, which involves preparing stories to run when someone prominent dies.

ABC is also sending 'Good Morning America' weekend anchor Bianna Golodryga to cover the story.

Already, executives at CBS News have met to map out a plan for Royal wedding coverage, said David Friedman, executive producer of 'The Early Show'. They'll need to scout sites for locations near the wedding and make sure experts are booked.

Producers at 'The Early Show' were running down their morning lineup at 6.15am on Tuesday when word came from the network's London office: There's an engagement. Staff members scrambled to find people to talk about the couple and restructured the show with 45 minutes' notice, he said.

"American viewers love stories about the Royals," Friedman said. "They always have and they always will."

It's a feel-good story, which have been in short supply since the wedding of Chelsea Clinton, he said.