Hungary had demanded the mammoth sum to meet half the cost of installing border fences in 2015 at the height of the migrant crisis.
But the European Commission chief hit back yesterday, saying the country has repeatedly turned down help to tackle the crisis.
In a scathing letter, Jean-Claude Juncker told right-wing prime minister Viktor Orban that “solidarity is a two-way street”.
He wrote: “There are times in which member states may expect to receive support, and times in which they, in turn, should stand ready to contribute.
“And solidarity is not an a-la-carte dish; one that can be chosen for border management, and rejected when it comes to complying with relocation decisions that have been jointly agreed.
“The Commission, and I personally, remain committed to working together with Hungary towards a more efficient and fairer European migration and asylum policy, based on responsibility and solidarity.
“I count on your active contribution, on the basis of our EU treaties and our common values.”
Unelected Mr Juncker said Hungary turned down a 2015 offer to “benefit from [the] relocation of 54,000 persons” as part of an emergency scheme.
Mr Orban’s government returned “nearly €4million (£3.6m) of EU funds” under the relocation programme, the bureaucrat added.
He also insisted 20 European border guards are deployed at Hungary’s border with Serbia to help control migrant flows.
Mr Juncker added: “At this stage, to the Commission’s knowledge, the European Border and Coast Guard has not received any request from Hungary to increase this contingent.”
But the Eurocrat admitted Brussels could provide emergency funds to strengthen Hungary’s borders “in case of specific urgent needs”.
In the letter, obtained by Politico, he wrote: “The Commission is ready to swiftly examine [any] request and provide the appropriate assistance for a strengthened border control carried out in accordance with EU law.
“To respond to the migration crisis, the Commission has provided such emergency assistance to Bulgaria, Greece, Italy and Spain, following the examination of their applications.”
Mr Orban, a fierce opponent of Brussels, has been campaigning against migration for several years.
Hungary is currently refusing to accept an EU-imposed migrant quota, along with eastern neighbours Slovakia.
The pair were taken to court by the European Commission, and today an appeal by the pair was rejected in the European Court of Justice.
Mr Orban’s tough rhetoric has seen his right-wing party Fidesz secure a firm lead in opinion polls ahead of next year’s Hungarian election.
There are currently less than 700 migrants in the country, according to recent statistics.
More than half of these – a total of 430 – are kept in two closely guarded container camps on the Serbian border.