Meghan Markle will attend Pippa Middleton's wedding. But there's a catch.

If you’ve been waiting for a sign that things between Suits actress Meghan Markle and Prince Harry are getting pretty darn serious, this is it.

Just five months ago, Kensington Palace confirmed the 32-year-old prince was dating the US actress.

Now, it seems Meghan has scored herself an invite to the most anticipated wedding of the year: Pippa Middleton's upcoming nuptials to financier James Matthews.

But - there's a catch.

While 35-year-old Meghan has been invited as Harry's plus-one, she will not be attending Pippa's ceremony at St Mark’s church in Engelfield, England, on May 20.

PEOPLE magazine confirmed the news, with a source revealing that protocol prohibits Meghan from attending the ceremony because she and Harry are not engaged.

Ah yes, that pesky "no-ring, no-bring" rule rears its head.

The actress will, however, be by her partner's side at the less formal bash after the official part of Pippa and James' church ceremony is complete.

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Need further proof Meghan may be our very next Princess?

Over the Easter weekend, Prince Harry skipped the royal tradition of attending Easter services at St George's chap with Queen Elizabeth II and instead flew to Toronto to spend the weekend with his girlfriend.

Now that Meghan is allowed to attend, Pippa's May nuptials are shaping up to be quite the family affair.

Just last week, Kensington Palace confirmed that Pippa's royal niece and nephew - Prince George and Princess Charlotte - are joining the bridal party as page boy and bridesmaid, respectively.

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