WARSAW, Poland (AP) — Polish President Andrzej Duda unexpectedly said Friday that he was proposing urgent amendments to a contentious law on Russian that he signed this week and that drew U.S. and European Union criticism.

Duda said he was aware of the controversies, also in Poland, surrounding the law proposed by the governing conservative Law and Justice party and was addressing them by sending amendments to the parliament on Friday. He urged the lawmakers to act swiftly.

Critics say the law violates the Polish Constitution and could keep government opponents from holding public office without full power to challenge the decisions in court. They say it could also have a negative effect on the eligibility of opposition candidates in an election due in the autumn.

In its current form, the law will create a powerful committee, ostensibly meant to investigate Russian influence in Poland but is seen as primarily targeting Donald Tusk, a former prime minister who is now opposition leader. Law and Justice accuses Tusk of having been too friendly toward Russia as prime minister between 2007 and 2014, and making gas deals favorable to Russia before he went to Brussels to be the president of the European Council between 2014 and 2019.

The U.S. State Department and the EU authorities have strongly criticized the law and expressed concerns about Poland's democracy. The 27-member EU, which Poland joined in 2004, also threatened to take measures if it became fully clear that such a law would undermine democratic standards.

Duda said Friday that his amendments ensured that the law was reviewed by nonpartisan experts, and that no lawmakers would sit on the commission and that its findings wouldn't ban anyone from holding public offices. He said he is also strengthening the right to appeal before a court by those people who were under investigation.

The commission is meant to present a report on its findings by Sept. 17, just weeks before the election — expected in October or November — and could impose punishments, including 10-year bans on officials from positions that have control over spending public funds.

Duda signed the law, dubbed by critics “Lex Tusk,” on Tuesday and it will take effect a week from its publication.

Bowing partially to critics who say the law is unconstitutional, Duda said earlier this week that he was also sending it to the Constitutional Tribunal to review the bill for conformity with the supreme law.

Duda, aligned with the Law and Justice, said Friday he was reacting to the public outcry over the law.

Law and Justice party leader Jaroslaw Kaczynski and Tusk are longtime political rivals.