NEW DELHI: India plans to send four senior ministers to Ukraine's border nations, a government source said on Monday, to help in the rescue of thousands of its citizens who remain trapped more than four days after Russia's invasion of the country.

Prime Minister Narendra Modi met senior officials on Monday to discuss evacuation efforts, amid rising concerns back home about the safety of some 16,000 Indians still in Ukraine, most of them students.

Ministers Hardeep Puri, Jyotiraditya Scindia, Kiren Rijiju & VK Singh will travel to neighbouring countries of Ukraine to coordinate the evacuation, according to an Indian government source.

Indians make up about a quarter of the 76,000 foreign students studying in Ukraine, mainly on medical courses, according to official estimates.

Thousands of African students are also stranded in the country.

Late on Sunday night, India's embassy in Poland issued an advisory, saying it had arranged for buses at the Shehyni border in Ukraine, for those stranded there, to cross over into Poland.

Opposition leaders and parents of students have urged Modi to take urgent measures to evacuate the remaining students out of Ukraine.

"We can't abandon our own people," opposition lawmaker and Modi's main opponent, Rahul Gandhi said in a tweet on Monday, asking that federal government share a detailed evacuation plan.

Fears of being caught up in the fighting, long traffic jams and severe weather meant students were reluctant to heed the Indian government's suggestion they make their own arrangements to reach the border with Poland, Romania or Slovakia, Reuters reported on Friday.