Qatari Labor Minister Ali bin Samikh al-Marri said Qatar already has a fund to deal with worker deaths and injuries.
He told AFP that Qatar is already handing out hundreds of millions of dollars in unpaid wages, and accused the Gulf state's critics of "racism."
Human rights groups accuse Qatar of under-reporting deaths. The government strongly disputes reports that thousands have died on construction site accidents or from heat-related illnesses in the country's searing summer temperatures.
Amnesty International and Human Rights Watch have led demands for FIFA and Qatar to create a fund for workers matching the $440 million World Cup prize money.
But some international trade union leaders have said a new fund would be too complicated to set up and manage.
Meanwhile, Minister al-Marri has said "Every death is a tragedy," adding: "There is no criteria to establish these funds."
"Where are the victims, do you have names of the victims, how can you get these numbers?" he asked.
Qatar has faced a barrage of criticism since it was named as a surprise World Cup host in 2010, and attacks have increased this year over migrant workers, LGBTQ freedoms and women's rights.
Last month, Qatar's emir said the country was facing an "unprecedented campaign" of criticism ahead of the November 20 kick-off.
al-Marri said detractors had ignored reforms implemented since 2017 with the help of the International Labour Organization, a UN agency.
Other countries and groups have used "false information" and "rumors" to "discredit Qatar with deliberately misleading claims," he said.
The 'Kafala' employment system that opponents said was near slavery has been virtually dismantled in Qatar, the government said. Workers can now change jobs and leave the country without their employer's permission.
The government has established a minimum wage of 1,000 riyals ($275) a month, and passed laws against trafficking and limiting the hours that can be worked in extreme heat.
"After all this effort, all these reforms, people still attack us," the minister said.
The ILO this week said unpaid wages were workers' biggest complaint, and that Qatar's main challenge is to apply its new laws. al-Marri said his ministry was "focused" on the task.
"If a salary payment is delayed for one month, we will pay from the fund and take action," he said, adding that owners of blacklisted companies had been fined and jailed.
Forty-two recruiting agencies accused of exploitation have been closed, the tribunals hearing complaints have increased from three to five and extra labor inspections have been ordered on hotels and other industries during the World Cup.
The minister said he was discussing making the ILO's office in Doha permanent, and that Qatar wants to host an annual dialogue on protecting migrant workers.
"We lead the region now for migrant reforms," al Marri said. "We have good relations with our neighbors, and we can exchange best practices."