"We reached agreement. I am going to Luxembourg," he said on Monday as he left the headquarters of his ruling Justice and Development Party (AKP).
EU foreign ministers have been haggling over the text since Sunday evening in Luxembourg.
A Turkish official said Turkey approved the EU text on the conditions under which it will hold membership talks with the bloc.
"The preparations are in place so that the minister can travel to Luxembourg," he said. Gul had been waiting to fly out of Ankara once satisfied with the document.
A spokesman for the British EU presidency declined to confirm an accord by all sides, but reiterated that Brussels still hopes to start the landmark membership talks later on Monday.
"We would very much like if possible to start these talks today, or within the next hours," said the spokesman, adding that EU ministers were due to meet again in formal session shortly to discuss the latest developments.