Duda announced his proposal at a news conference in the presidential palace in Warsaw, Polish state news agency PAP reported.
The president said he was sending amendments to parliament because he was aware of the domestic and international criticism surrounding the law proposed by Poland's governing conservative Law and Justice (PiS) party.
He said the amendments would reach parliament on Friday and called on lawmakers to “approve them as soon as possible.”
No lawmakers on Russian influence panel, easier appeals, no bans
Duda said he was proposing to "amend the law in three ways."
First, the “commission for investigating Russian influence on Poland's internal security between 2007 and 2022” should not include MPs and senators, he said.
Second, the commission’s decisions should be appealable to common courts rather than administrative ones, which can only determine a decision’s legality, he added.
“Additionally, to dispel any doubts, a person investigated by the commission would be allowed to lodge an appeal with their local appeals court, so that cases are not necessarily judged by the Appeals Court in Warsaw,” he told reporters.
Third, the commission would be stripped of the right to impose “counter-measures,” such as a ban on holding public office, a ban on access to state secrets or a ban on owning weapons, Duda said.
The president told reporters: “Instead I propose that the commission be allowed to state that a person who has been found to be acting under Russian influence does not guarantee the proper performance of public duties."
Effort to 'strengthen the transparency of the commission's proceedings': president
Duda also said that his amendments were designed to "strengthen the transparency of the commission's proceedings.”
He told reporters: “Apart from exceptional cases involving the highest state secrets, all the hearings of the commission would be open to the public.”
“For me, the most important thing ... is to ensure that the public ... has access to information,” the president added.
Probe into Russian influence in Polish politics
The president's announcement came after he said on Monday that he had approved a law establishing a special panel to investigate Russian influence in Polish politics.
Duda approved the measure after it passed parliament last Friday on a final vote of 234 to 219, with one abstention, Polish state news agency PAP reported.
The president, who is an ally of Poland's conservative government, told reporters at the time that he had "no doubt that the issue of Russian influence needs explaining."
The US State Department and the European Union have since expressed concerns about the Polish law, which has caused a public outcry.
Critics have said it violates the Polish constitution and could keep government opponents from holding public office and block opposition candidates in an election due in the autumn, the AP news agency reported.
Polish opposition politicians said last week that the proposed probe was specifically targeted at former Prime Minister Donald Tusk, who is the leader of the country's largest opposition grouping, the Civic Coalition.
A spokesman for the country's ruling conservatives said on Wednesday that the new commission to investigate Russian influence in Poland could be appointed at the next session of parliament on June 9.
Friday is day 464 of Russia’s war on Ukraine.
Source: PAP, prezydent.pl