If you scroll through Instagram or Facebook, you will no longer see ads urging you to try TikTok. Meta began blocking ads and paid messages from ByteDance on Thursday, Bloomberg first reported, and Meta confirmed it.

The ban covers the U.S., Canada, Egypt, Indonesia, Japan, Thailand and Vietnam. It also reaches outside advertisers who run campaigns that link to TikTok or other ByteDance apps in those places, CNA reported, and it took effect immediately.

Meta made no apology for the move. "We don't have to run ads from a competitor whose goal is to pull people off our apps," Meta spokesperson Chris Sgro said. "Declining promotional services to a competitor is a normal business practice across industries." TikTok and ByteDance did not respond right away to requests for comment.

The fight has been building for months. In August, Meta settled with U.S. states over harms to children and agreed to daily usage limits and nighttime curbs for kids on Facebook and Instagram. Since then, Meta has pushed TikTok and YouTube to adopt the same rules, Bloomberg reported. TikTok has stayed publicly silent on that campaign.

TikTok has also put up walls of its own. Last month it removed dedicated Instagram links from user profiles, Bloomberg reported. TikTok's own site says it does not support links that open rival social apps, CNA noted, though users can still link to their websites.

The two companies compete for the same thing, which is the attention of users and the advertisers who pay to reach them. TikTok has more than 200 million U.S. users and now runs in the U.S. through a majority American-owned joint venture, CNA reported. Meta, by contrast, cannot operate in China, TikTok's home market.

Other tech firms are doing the same. OpenAI told ad partners in September it would not accept ads for rival image and audio tools, according to a report cited by Bloomberg.

What we know: The ad ban is in force in seven countries.
What we don't: Whether TikTok will strike back or Meta will widen the ban.