After two years of negotiations, the bill was approved by the European parliament in May.
At Tuesday's meeting which lasted until midnight, lawmakers agreed on most parts of Article 6 of the draft AI Act, one of the stumbling blocks in talks, the sources said, declining to give further details on what was agreed.
Article 6 outlines the types of AI systems that will be designated "high risk", and therefore subject to greater regulatory scrutiny, the sources said.
Ahead of Tuesday's meeting, Reuters reported citing sources that European lawmakers were yet to agree on several issues leaving any deal off the table until December.
Failure to reach a deal could push negotiations to early next year, increasing the risk that discussions are further derailed by European parliament elections in June.
Dragos Tudorache, Brando Benifei, Benifei, Supantha Mukherjee, Martin Coulter, Elvira Pollina, Josephine Mason, Kirsten Donovan
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