Since VKontakte does not allow direct advertising to external messengers, the following options are suitable:
Multi-step funnel
Run ads on VKontakte to a VK landing page or VK bot.
Inside the bot (or on the landing page), offer the user to “get more information/gift/continuation” → and provide a button with a link to the Telegram bot.
The user clicks on it and goes to Telegram on their own.
Links in content
In private messages, posts, or pinned posts, you can leave a link to the Telegram bot.
It’s better to disguise it as “Learn more here” or “Get the materials.”
Using intermediate pages
In ads, use a link to a mini-landing page.
On it, place a button “Go to Telegram.”
VKontakte does not block such transitions because the ad leads to a website.
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