Zendaya and Tom Holland are very much still a couple -- something they proved this week by holding hands after her big movie premiere in London ... squashing all the rumors.

Tom was firmly holding Zendaya's hand Thursday night as he led her away from the "Dune: Part Two" afterparty ... leaving paps and autograph hounds in the dust as he helped her into a waiting car. Indeed, he's taking the lead here ... and certainly playing the BF role.

This is the first time Zendaya and Tom have been spotted together in public since the incessant breakup rumors first started -- until now, they've kinda been apart ... even when they've been in the same city of late.

Remember, the rumblings began in December when Z unfollowed everyone on IG ... even purging Tom from her social media with no explanation.

Tom told a photog, explicitly, they were not dunzo earlier in January -- and a couple weeks ago, he doubled down with some social media posts doting on Z. But, we still hadn't seen them at the same place at the same time until Zendaya's big moment at the premiere.

Now it's clear as day, Z and TH are going strong ... and there's no trouble in paradise.

They're historically a pretty private couple too, so this is a strong message as far as these two are concerned. Seems like Tom wanted to send a message once and for all.

Zendaya and Tom were wearing matching black outfits Thursday night ... and Zendaya looked a helluva lot more comfortable than what she showed up to the premiere wearing.