The EU institutions have been at odds with Warsaw about its justice reforms for years now, with the Commission warning they endanger the independence of the judiciary.
The European Court of Justice (ECJ) has halved the daily fine imposed on Poland because of its controversial reform of the judiciary.
On Friday, the European Commission said that Warsaw "has largely implemented the steps required" by the EU's top court. The Eastern European country has so far lost more than half a billion euros in its standoff with Brussels.
"The fines have been collected from 3 November 2021, that is when the fine started," Christian Wigand, European Commission spokesperson, said on Friday.
"And until yesterday this was a €1 million fine and from today it has been reduced to half a million."
The EU institutions have been at odds with the conservative Polish government about its justice reforms for years now, which the Commission says endanger judicial independence.
The court said in a statement on Friday that its latest decision came after a 10 March request from Warsaw to "revoke or, in the alternative, to modify the order" it had previously imposed because of legislative changes the government had rolled out.
It argued that "the measures adopted by Poland are not sufficient to ensure the execution of all the interim measures provided for in the order of 14 July 2021."
One outstanding issue is the so-called disciplinary chamber - a body, composed of largely political appointees, which has the power to sanction judges.
A ruling by the ECJ declared this body illegal, saying that Poland must dismantle the chamber. The daily fine was issued after Poland refused to do so.