"Russia is ready to continue and increase cooperation with the United States on a solid international legal basis to reach a peaceful settlement of the Syrian conflict," Antonov said.
So far, Russia-US cooperation on Syria has been largely limited to the hotline preventing incidents in Arab Republic's airspace, as well as the agreement on the creation of a safe zone in the country's south.
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According to Antonov, Moscow had decided to send an invitation to the US and UN Security Council members to participate as observers in the Syrian National Dialogue Congress.
"We consider the Congress as a forum designed to give serious impulses to the negotiation process under the auspices of the United Nations in Geneva and to the achievement of the accords by the Syrians themselves by mutual agreement and without preconditions," Antonov said. "We call on international and regional players that have an influence on the development of the situation in Syria to take an unambiguous position in support of the Congress."
The ambassador stated that the existing deconfliction mechanism between Russia and the United States in Syria should remain despite the withdrawal of a significant part of the Russian troops from Syria, and may be expanded to the ground operations.
"I do not think that the Memorandum of Understanding signed in October 2015 should be abolished or replaced. Rather, it may be expanded, primarily to the operations on the ground," Antonov said. "We proposed such ideas to the united States. But the United States, referring, in particular, to the National Defense Authorization Act, evaded these proposals."
Russia and the United States used to chair the International Syria Support Group (ISSG), which became the first steps in the Syrian settlement process. However, the US administration changed in early 2017, and the new president did not show any clear intention to be particularly involved in the Syrian issue. The three states which have a strong interest in and influence on Syria – Russia, Turkey, and Iran – decided to use this window of opportunity by taking the settlement process into their own hands.
On Russia-US Relations
According to the ambassador, President Donald Trump did not give up on his goal to improve US ties with Russia even though bilateral relations have deteriorated over the past year.
"Donald Trump came to power with the goal to improve bilateral ties," Antonov said on Thursday. "I am sure that the president did not give up on that goal. But he was unable to reach it."
Antonov added that "US-Russia ties have deteriorated over the past year as they have become a hostage of the internal political fight in the United States."
Russia does not tolerate foreign pressure and reacts to hostile actions, but at the same time Russian diplomats are not looking to escalate confrontations and are open to improving dialogue between the two countries, Antonov said.
"Russia does not accept US attempts to increase pressure and strongly reacts to unfriendly actions," Antonov said. "However, Moscow does not aim to cause confrontation and remains open to improving the bilateral dialogue. It can be achieved if the states build relationships on a basis of equality and mutual respect."
The United States and Russia have multiple avenues of cooperation, including the need to combat weapons proliferation globally, stabilize the situation in Syria, denuclearize the Korean Peninsula and eradicate sources of global tensions, Antonov said, adding that the two countries were not adversaries, but strategic partners whose partnership had been tested over time.
"I firmly believe that we [Russians] are not enemies or opponents of the United States despite the fact that some promote such a narrative," Antonov said. "We are partners who have been tested by time, partners whose friendship was tested in combat and by the 'spirit of the Elbe’," Antonov said.
The two countries should focus on enhancing partnership in the fight against terrorism and improving coordination between intelligence services, the diplomat said.
"One of the key priorities is to develop real anti-terrorism coordination and provide stronger cooperation between intelligence agencies of our countries," Antonov said.
Besides enhancing the counterterrorism partnership on a bilateral level, Russia is interested in growing such cooperation in the context of Russian President Vladimir Putin's initiative to establish an international counter-terrorism coalition, he added.
Antonov emphasized that the United States and Russia have no obstacles for such cooperation, adding that the necessary regulatory framework for agreements that would ensure the national security of both states had been created.
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On December 15, Russia's Federal Security Service (FSB) said it had prevented a terrorist attack by Daesh supporters in Saint Petersburg.
Shortly after the operation, Russian President Vladimir Putin called US President Donald Trump to thank him for the advanced warning the United States intelligence agencies provided to Moscow, while Trump said US agencies were pleased to assist in preventing a terror attack.
INF Treaty
Speaking about the Cold-War era Intermediate-Range Nuclear Forces (INF) Treaty, Antonov stated that Washington avoided "substantive" talks on Russia's concerns about the US shortfalls in implementing the missile treaty.
"We are convinced that aggressive public rhetoric used by Washington is counterproductive and does not contribute to strengthening the INF," he added.
"A complicated situation has arisen around the treaty on medium- and short-range missiles. Washington continues to politicize this issue, reinforcing its line of publicly accusing Russia of ‘violating’ the INF," the senior diplomat said.
Russia’s proposal to make the Intermediate-Range Nuclear Forces (INF) Treaty multilateral remains relevant today, particularly because of the changes in international security since the treaty conclusion, he stated.
"In 2007, Russia proposed that the INF Treaty become multilateral. Unfortunately, our proposal was not supported by the European countries — the US allies in the NATO bloc," Antonov said.
The INF was signed back in 1987 by the United States and the then-Soviet Union to prevent the use of nuclear and conventional missiles with an intermediate range, defined as 500 to 5,000 kilometers (310 to 3,100 miles).
START Treaty
According to Antonov, Moscow has questions over the United States' fulfillment of the New Strategic Arms Reduction Treaty (START), specifically on the re-equipment of some of the strategic offensive weapons, however, the dialogue between the countries continues.
"As for the fulfillment of the Treaty terms by the United States, we have questions. In particular, with regard to the re-equipment of part of the US strategic offensive arms," Antonov said. "As Russian President Vladimir Putin said on January 11, this is possible only if able to verify that there was no potential for reverse conversion of such objects. So far, Russia has no such evidence, and this causes some concern."
"We continue the dialogue on these issues with the American side. We hope that the United States will also unequivocally fulfill its obligations under the Treaty," the ambassador added.