Ukraine's top prosecutor has called on Brazilian authorities to arrest Russian President Vladimir Putin should he attend the upcoming G20 summit in Rio de Janeiro, citing an international warrant for his arrest.

Andriy Kostin, Ukraine's Prosecutor General, told Reuters he had received intelligence suggesting Putin may attend the November meeting of the world's leading economies. Kostin emphasised Brazil's obligation as a signatory to the Rome Statute to enforce the arrest warrant issued by the International Criminal Court (ICC) in March 2023.

"It's important for the international community to stand united and hold Putin accountable," Kostin said. "I truly hope that Brazil will arrest him, reaffirming its status as a democracy and a state governed by the rule of law."

In March 2023, the Hague-based tribunal accused Putin and child commissioner Maria Lvova-Belova of the war crime of deporting children from Ukraine, a charge the Kremlin has dismissed as "null and void". Russia denies all allegations of war crimes in Ukraine.

Kostin warned that failing to act on the warrant could set a dangerous precedent, allowing leaders accused of serious crimes to travel with impunity.

The Kremlin has not confirmed Putin's attendance at the summit. When asked about the Russian leader's plans, spokesman Dmitry Peskov told reporters, "No. When a decision is made, we will let you know."

Likewise, Brazilian officials have indicated that while Putin received a standard invitation to the November 18-19 meetings, there has been no confirmation of his attendance. Brazil, as a signatory to the Rome Statute since 2002, is theoretically obliged to execute the ICC warrant.

However, the situation has shades of grey. Brazilian President Luiz Inácio Lula da Silva last year suggested Putin could attend "easily" without risk of arrest, before backtracking under international pressure. Lula later questioned Brazil's own participation in the ICC, noting that major countries like the United States and Russia are not signatories.

The warrant has already had an impact on Putin's international travel. He opted for a virtual appearance at last year's BRICS summit in South Africa, another ICC member state, likely to avoid potential arrest. In contrast, Putin did visit Mongolia in September, despite its ICC membership, highlighting the challenges in enforcing such warrants.

Reacting to the trip, Ukrainian foreign ministry spokesman Georgiy Tykhyi stated, "Mongolia allowed the indicted criminal to escape justice, thereby sharing responsibility for his war crimes. We will work with partners to ensure this has consequences for Ulaanbaatar.”

Mongolian officials responded by candidly admitting that they could not antagonise Moscow because their country is heavily dependent on energy imports from Russia.

Brazil finds itself in a very different position, being historically wary of upsetting the West and with Russia only ranking among its 15 largest trading partners. Still, President Lula – whose attendance at next week’s BRICS summit in Kazan has been confirmed – may want to send a signal to the world by hosting the Russian leader in line with his often-proclaimed neutrality.

"It is important for Brazil to stay out of this conflict and advocate for a peaceful resolution. Those who wish to speak with us now could have done so before the war started," he recently said, stressing how, while condemning Moscow’s invasion, he planned to push for a negotiated settlement for the war in Ukraine. However, Brazil's peace plan mooted last month with China was rejected by Ukrainian President Volodymyr Zelenskiy, who slammed it as a "half-hearted scheme serving the interests of Moscow."

As the G20 summit approaches, the international community watches with keen interest. The potential presence of Putin at the Rio meeting will be a litmus test for Brazil's commitment to international law and justice.