Prime Minister Narendra Modi has asked the Indian Air Force (IAF) to evacuate Indians stranded in Ukraine due to the Russian military offensive against that country, sources said on Tuesday.

The IAF is likely to deploy several C-17 aircraft as part of Operation Ganga from Tuesday, they said. The sources said the IAF is keeping its aircraft on standby to launch the evacuation operation at short notice.

In order to scale up the ongoing evacuation efforts under Operational Ganga, Modi has called for the IAF to join the exercise, the sources said. Leveraging the capacities of the IAF will ensure that more people can be evacuated in a shorter time frame, they noted.

The large C-17 aircraft will also help deliver humanitarian aid to war-hit Ukraine more efficiently, they said. C-17 is IAF's largest transport aircraft and it has the capacity to carry approximately 300 passengers in it during a humanitarian relief mission.

Till now, only private Indian carriers have been evacuating Indians from Romania and Hungary, countries with land borders with Ukraine on the western side, as the Ukrainian airspace has been shut since February 24. India began evacuation of around 14,000 of its stranded citizens on February 26.

In a statement on Tuesday, the IAF said it is geared up for any requirements of evacuation of Indian citizens from Ukraine.

Indians are travelling by road to Ukraine's borders with Romania, Hungary, Slovakia, Poland etc, from where they are being taken by the Indian government officials to the airports for the evacuation flights.

The Indian Embassy in Ukraine on Twitter advised all Indian nationals -- including students -- to leave Kyiv urgently on Friday itself, preferably by available trains or through any other means available.

Leave Kyiv, Indian embassy in Ukraine tells students

The Indian embassy in Ukraine on Tuesday asked stranded Indians in Kyiv to leave the capital city urgently.

In an advisory, it asked the citizens to leave Kyiv by available trains or any other means.

"All Indian nationals including students are advised to leave Kyiv urgently today. Preferably by available trains or through any other means available," the embassy said.

The advisory came amid increasing fighting between Russian forces and Ukrainian troops around Kyiv.