Ukraine is aiming to hold a peace summit by the end of February – preferably at the United Nations with its secretary general, António Guterres, as a possible mediator – according to its foreign minister.

But Dmytro Kuleba said that Russia could only be invited if the country faced a war crimes tribunal first.

Kuleba also said he was “absolutely satisfied” with the results of President Volodymyr Zelenskiy’s visit to the US last week, and he revealed that the US government had made a special plan to get the Patriot air defence system, which can shoot down enemy missiles, ready to be operational in the country in less than six months. Usually, the training takes up to a year.

Kuleba said during the interview at the foreign ministry that Ukraine will do whatever it can to win the war in 2023, adding that diplomacy always plays an important role.

“Every war ends in a diplomatic way,” he said. “Every war ends as a result of the actions taken on the battlefield and at the negotiating table.”

Kuleba said the Ukrainian government would like to have a peace summit by the end of February, around the anniversary of Russia’s invasion.

“The United Nations could be the best venue for holding this summit, because this is not about making a favour to a certain country,” he said. “This is really about bringing everyone on board.”

On 12 December, Zelenskiy said that Ukraine planned to initiate a summit to implement the Ukrainian peace formula in 2023.

At the Group of 20 summit in Bali in November, Zelenskiy presented a 10-point peace formula that included the restoration of Ukraine’s territorial integrity, the withdrawal of Russian troops, the release of all prisoners, a tribunal for those responsible for the aggression and security guarantees for Ukraine.

Asked about whether they would invite Russia to the summit, the foreign minister said that Moscow would first need to face prosecution for war crimes at an international court.

“They can only be invited to this step in this way,” Kuleba said.

About Guterres’ role, Kuleba said: “He has proven himself to be an efficient mediator and an efficient negotiator and, most importantly, as a man of principle and integrity. So we would welcome his active participation.”

He again downplayed comments by Russian authorities that they are ready for talks.

“They regularly say that they are ready for negotiations, which is not true, because everything they do on the battlefield proves the opposite,” he said.

Zelenskiy’s visit to the US was his first foreign trip since the war started on 24 February. Kuleba praised Washington’s efforts and underlined the significance of the visit.

“This shows how both the United States are important for Ukraine, but also how Ukraine is important for the United States,” said Kuleba, who was part of the delegation to the US.

Ukraine secured a new $1.8bn military aid package, including a Patriot system, during the trip.

Kuleba said that the move “opens the door for other countries to do the same”.

He said that the US government developed a programme for the air defence system to complete the training faster than usual “without any damage to the quality of the use of this weapon on the battlefield.”

While Kuleba didn’t mention a specific time frame, he said only that it will be “very much less than six months”. And he added that the training will be done outside Ukraine.