Nikola Selaković signed a bilateral agreement, dubbed the Consultation Plan, with his Russian counterpart on the sidelines of the UN General Assembly session in New York on Friday.
Serbia's foreign minister on Sunday sought to play down the importance of an agreement with Russia after the Balkan state that is seeking European Union membership faced criticism for signing it.
Nikola Selaković signed the agreement on Friday along with Russian Foreign Minister Sergey Lavrov on the sidelines of the UN General Assembly meeting in New York.
The agreement, dubbed the Consultation Plan, is meant to define the relations between the two foreign ministries for 2023 and 2024.
Most Western delegations shunned Russia's top diplomat over the country's invasion of Ukraine.
Selaković said at a news conference on Sunday that the agreement is a "technical" one and relates to bilateral ties, but not security issues. Serbia has been signing similar documents with Russia since 1996, Selaković insisted.
"The government could have rejected such a plan but there is nothing contentious in it," he added. "It is being criticised by those who haven't seen it."
The signing of the document in New York marks the first agreement of any kind the two countries have signed since Moscow's full-scale invasion of Ukraine in late February.
MEPs slam Selaković's move as 'serious blow' to Serbia's EU path
Serbia is officially a candidate for EU membership, but the government maintains good relations with Russia and China.
It is also one of a handful of European countries -- including Bosnia, Moldova and Belarus -- that have not followed the EU's lead in placing Russia under sanctions for its war in Ukraine.
However, Belgrade voted three times for UN resolutions that condemned Russia’s invasion of Ukraine and suspended it from the main UN human rights body.
The news of the deal triggered harsh criticism from the pro-EU opposition at home and some EU politicians.
A member of the European Parliament from Germany's Greens, Viola von Cramon, suggested the possible suspension of EU accession talks with Serbia.
"This is a serious scandal," von Cramon said on Twitter. "In the midst of raging war, (the Ministry of Foreign Affairs of) Serbia signs the plan on future collaboration with the aggressor."
Von Cramon added that "maybe it's just a signal for us to freeze the EU accession talks as entering the EU does not go through Moscow."
Another MEP, Vladimir Bilčik from Slovakia, described the agreement with Russia as a "serious blow" to the accession process in the Western Balkans.
Bilčik, a member of the EPP group in the European Parliament, also serves as the rapporteur for Serbia, whose task is to rate European Commission's annual report on the country's progress towards full membership and present it to the parliament for adoption.
The Serbian government is in technical mandate after the most recent election in April.
Current Prime Minister Ana Brnabić was given the green light by President Aleksandar Vučić to continue in her role, and she is expected to nominate the new cabinet soon.
However, it is unclear whether Selaković will keep his post as minister of foreign affairs or remain in the government altogether.