The UK has enough support from other EU members to block attempts to impose a 40% female quota on company boards, according to a media report.
Nine European countries sent a strongly worded letter to the European Commission's (EC) president opposing the proposal which would apply to all listed companies in the EU, the Financial Times (FT) said.
These members - including the Netherlands, Malta and six central and eastern European countries - represent sufficient votes to block the plan under the EU's complex voting process, and could lead Brussels to drop the legislation.
The EC was hoping to introduce quotas to correct the gender imbalance on company boards after research it published this year revealed that just one in seven board members at Europe's top companies is a woman.
The letter urges the EU not to legislate an issue which the countries argue is already being dealt with on a national level, the FT reported.
"We agree with the commission's stance that there are still too few women on the boards of publicly listed companies," a draft version of the letter said, according to the FT.
"(But) we reiterate that any targeted measures in this area should be devised and implemented at national level.
"Therefore, we do not support the adoption of legally binding provisions for women on company boards at the European level."
A number of countries across the 27-member bloc have already imposed national quotas, including France, Italy, Spain and the Netherlands, but the UK has always been strongly opposed to such measures.
Earlier this year, the Government said: "We do not think it is right to consider introducing quotas while some member states are successfully pursuing voluntary approaches.
"We believe that self-regulation should be allowed to prove that it can radically increase the number of women on European boardrooms."
Germany and Sweden did not sign the letter, the FT said, but ministers from these countries said they would not support an EU-wide quota system.