Spanish Prime Minister Pedro Sanchez on Wednesday announced the creation of a tool to track hate speech on social media and hold them accountable, in his latest measure targeting tech giants.

The tool "will make it possible to systematically measure the presence, evolution and reach of hate speech on digital platforms" with "recognised academic criteria", Sanchez told a Madrid forum dedicated to the topic.

Dubbed "Hodio", the tool will generate a report every six months with a table ranking each platform, according to the Spanish Observatory of Racism and Xenophobia, which will be responsible for implementing it.

"We will publicly display the results so that everyone knows who stops hate, who looks away and who makes a business out of hate," said Sanchez.

"From now, I think social media must be held publicly accountable for every piece of hate content they allow," the Socialist leader added, saying hate crimes in Spain had increased by 41 percent in the last decade.

Sanchez is an outspoken critic of the power of big tech companies and their bosses, regularly referring to them as "techno-oligarchs".

In February, he announced a plan to ban social media for under-16s, sparking a spat with X owner Elon Musk and Telegram founder Pavel Durov.

His government has also asked the Spanish public prosecutor's office to investigate X, Meta and TikTok for possible offences related to AI-generated child pornography.