President Salome Zourabichvili of Georgia said on Saturday that she had vetoed a bill on foreign influence that has sparked protests and plunged the nation into a political crisis, threatening to derail its pro-European aspirations in favor of closer ties with Russia.

Georgia’s Parliament, which passed the draft law in three readings, is widely expected to override the veto. The ruling Georgian Dream party, which introduced the proposed legislation, can turn it into law as early as May 28, when the Parliament will be in session again.

Mrs. Zourabichvili called her veto “symbolic,” but it still represented another step in the political conflict between the country’s pro-Western opposition, which Mrs. Zourabichvili supports, and the Georgian Dream party, which has been in power since 2012.

The crisis has highlighted the highly polarized nature of Georgia’s political life. It has called into question the country’s pro-Western course, which is enshrined in its Constitution, as American and European officials threatened to downgrade ties with the country and impose sanctions on its leadership if the law were to be finalized and protests against it were crushed.

Georgia, a mountainous nation of 3.6 million in the middle of the Caucasus, once was a pro-Western trailblazer among former Soviet states. If it were to turn away from the West in favor of a closer relationship with Russia, the geopolitics of the whole region could change, because of the country’s central geographical position there.

The draft law that triggered the crisis bears an innocuous-sounding name: “On Transparency of Foreign Influence.”

It requires nongovernmental groups and media outlets that receive more than 20 percent of their funding from foreign sources to register as “organizations carrying the interests of foreign power,” and to provide annual financial statements for their activities. Georgia’s justice ministry would be given broad powers to monitor compliance. Violations could result in fines equivalent to more than $9,000.

The ruling party insists that the bill is necessary to strengthen Georgia’s sovereignty against outside interference in its political life by Western-funded NGOs and media organizations. But the country’s vocal political opposition refers to it as the “Russian law,” designed to convert Georgia into a pro-Moscow state in substance, if not in name.

“This law, in its essence and spirit is fundamentally Russian, contradicting our constitution and all European standards,” Mrs. Zourabichvili said in announcing the veto on Saturday. “This law is not subject to any changes or improvements, making it an easy veto,” she said in televised remarks. “This law must be repealed.”

In 2018, Mrs. Zourabichivili was endorsed by the Georgian Dream party in her successful bid to become president. But in the years since then, Mrs. Zourabichvili has grown increasingly critical of the party’s policies, a process of mutual alienation that peaked with the party’s failed attempt to impeach her in 2023.

Born in Paris to a family of prominent Georgian émigrés who fled the 1921 Bolshevik occupation of the country, Mrs. Zourabichvili, in her first official role in Georgia, was France’s ambassador there in 2003. The following year, she accepted Georgian nationality and became the country’s first female foreign minister, a role she filled until Oct. 2005. Before becoming Georgia’s president, Mrs. Zourabichvili also founded her own political party and was elected to Parliament in 2016.

While her role is largely ceremonial, Mrs. Zourabichvili has become the public face of the protest against the domination of the Georgian Dream party, as opposition parties in Georgia have suffered internal splits.

Since the draft law was introduced in early April, the country’s capital, Tbilisi, has become engulfed in protests against it. Protesters, many of them students, have marched through the streets of Tbilisi almost every day shouting, “No to the Russian law.” They have repeatedly surrounded the country’s imposing Soviet-era Parliament building on Rustaveli Avenue and tried to block entrances to it.

Many protests turned violent as riot police officers pushed the protesters away from the Parliament building, often using tear gas, pepper spray and fists to disperse them. Many members of the opposition were arrested and beaten. Some reported being harassed and intimidated by the authorities. On Saturday, following Mrs. Zourabichvili’s veto, protesters again filled the square in front of the Parliament.

At the end of April, the ruling party, led by Bidzina Ivanishvili, a reclusive oligarch who returned to Georgia in the early 2000s after making a fortune in Russia, organized a rally in support of the bill. On Friday, thousands of conservative Georgians also marched in a church procession through the city center to one of Tbilisi’s main cathedrals. Many of them said they supported the bill.

“I have friends in Ukraine, Russia, Moldova,” said Gocha Kekenadze, a farmer who came from the Kakheti region east of Tbilisi to join the procession. “We want to live as we did before” in the Soviet Union, said Mr. Kekenadze, 62. “It is the Americans who tell us to pick a rifle and fight against Russia.”