Deputy Foreign Minister Sergei Ryabkov says Russia respects Iran’s presence in Syria which he described as lawful amid reports that the US was pressuring Moscow on Tehran's role in the Arab country.

Ryabkov said Iran has been in Syria at the official request of the Syrian government to help the country fight terrorism, the Tass news agency reported Friday.

“We treat with great respect Iran’s steps to provide its own security and actions, including on Syria at the invitation of this country’s lawful government,” he said, adding there were however "prospects or space for further work in this sphere."

The official did not elaborate but his remarks came after a meeting between senior Russian and US delegations to discuss Syria in Geneva, Switzerland.

Ryabkov said Russia had many disagreements with the US over issues such as Syria, adding that Moscow was nonetheless ready to negotiate with Washington over the situation in the country.

"We’ve got many inconsistencies with the Americans in this area," the senior diplomat noted. "Approaches are directly opposite in some cases, but here as well, which is important, there are grounds for continuing dialogue regarding Syria."

Ryabkov reiterated that Russia is working with Iran on Syria in the Astana format. "In the near future, new contacts will take place, including on the Geneva platform, which we regard as an important component of greater work," he said.

Russia's Deputy Foreign Minister Sergei Ryabkov

The official said Russia had no intention to undermine the UN-led talks over Syria in Geneva, stressing that diplomatic discussions in Sochi and Astana were to be considered as complimenting the Geneva talks - a position which he said was shared between Moscow and Tehran.

"Sochi and Astana cannot replace Geneva; these are independent venues, and all these tracks complement each other. We presume that Tehran has similar views on it."

Iran has been in Syria on an advisory military capacity since the conflict erupted in the country in 2011. Russia joined the battle late in 2015. The two countries intervened in Syria at the official request of the Syrian government.

Washington, which deployed troops in Syria in 2014 despite repeated criticisms by Damascus, has been critical of Iranian and Russian role in the country.

Russia has reiterated that it will be ready to discuss the withdrawal of foreign forces from Syria when the US starts pulling out its own forces.

Russian Foreign Ministry Spokeswoman Maria Zakharova said on Thursday that Washington was maintaining an "illegal" military presence in Syria.

Responding to a question by Iran’s official IRNA news agency regarding US pressure for Iran’s withdrawal from Syria, Zakharova said the US should first pull out its own forces if it wants to discuss the fate of foreign forces in Syria.

Russian Foreign Minister Sergei Lavrov also said on Wednesday that all foreign forces staying in Syria without the legal consent of the Syrian government should leave the country.

“All foreign forces staying there without an invitation from the Syrian government must be eventually withdrawn,” Lavrov said in a press conference.