European Association chief Thierry Breton offered the remarks in a gathering with Mr Musk on Wednesday.
He said the online entertainment website would need to resolve issues like substance balance, disinformation and designated adverts.
The ever changing comes as the new regulation is set to come full circle.
Endorsed by the European Association recently, the Advanced Administrations Act is viewed as the greatest upgrade of rules administering on the web movement in many years, forcing new commitments on organizations to forestall maltreatment of their foundation.
Significant organizations are supposed to be in consistence with the law some time one year from now.
On the off chance that organizations are viewed as infringement, they face fines of up to 6% of worldwide turnover - or a boycott on account of rehashed serious breaks.
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In an explanation after the gathering, Mr Breton said he invited Mr Musk's confirmations that he would prepare Twitter to consent.
"Let's also be clear that there is still huge work ahead, as Twitter will have to implement transparent user policies, significantly reinforce content moderation and protect freedom of speech, tackle disinformation with resolve, and limit targeted advertising," he said.
"All of this requires sufficient AI (Artificial Intelligence) and human resources, both in volumes and skills. I look forward to progress in all these areas and we will come to assess Twitter's readiness on site."
The EU intends to lead a "stress test" in 2023 in front of a more extensive review, his office said.
Since his $44bn takeover of Twitter last month, Mr Musk has terminated a huge number of staff, restored previously restricted clients like Donald Trump and quit implementing different strategies, for example, rules pointed toward halting misdirecting data on Covid.
The moves have frightened a few social equality gatherings, who have blamed the very rich person for making strides that will increment disdain discourse, deception and misuse. A few organizations publicizing on the stage have ended spending in the midst of the worries - a significant disaster for the organization, which depends on such spending for the vast majority of its income.
In a blog entry on Wednesday, Twitter expressed none of its strategies had changed, yet that it was testing with an end goal to further develop the stage all the more rapidly and would depend more on moves toward limit the spread of material that disregard its principles - advertising "the right to speak freely of discourse however not opportunity of reach".
"Our trust & safety team continues its diligent work to keep the platform safe from hateful conduct, abusive behavior, and any violation of Twitter's rules," the organization added.
"The team remains strong and well-resourced, and automated detection plays an increasingly important role in eliminating abuse," it said.