India has had to walk a diplomatic tightrope over Ukraine in the past few days as it tried to balance its ties with Moscow and the West.

Delhi's first statement in the UN Security Council (UNSC) did not name any country directly but it said it regretted that calls from the international community to give diplomacy and dialogue a chance had not been heeded.

It, however, stopped short of criticising Russia. And before the UNSC voted on a draft UN resolution to condemn the invasion, Delhi faced calls from Russia, the US and Ukraine "to do the right thing".

Ukraine and Russia even issued public appeals for Delhi to take a clear stand. India chose to abstain from the vote but a careful reading of its statement suggests that it did go a step further and indirectly asked Moscow to respect international law.

India talked about the importance of "the UN Charter, international law, and respect for the sovereignty and territorial integrity of states", adding that "all member states need to honour these principles in finding a constructive way forward".

But India's decision to abstain raised questions, particularly in the West, over whether the world's largest democracy should have taken a clearer stand.

Former Indian diplomat JN Misra says India "has bad and worse options to pick from".

"One can't tilt both ways at the same time. India has not named any country, which shows it won't go against Moscow. India had to be subtle in picking a side and it has done that," he adds.

There are several reasons for India's quest to find a diplomatic balance over Ukraine.

The most important are India's time-tested defence and diplomatic ties with Moscow.

Russia continues to be India's largest arms supplier even though its share has dropped to 49% from 70% due to India's decision to diversify its portfolio and boost domestic defence manufacturing.

Also, Russia is supplying equipment like the S-400 missile defence system which gives India crucial strategic deterrence against China and Pakistan, and that is the reason why it went ahead with the order despite threats of looming US sanctions.

Moreover, it's hard for Delhi to overlook decades of history of diplomatic co-operation with Russia on several issues. Moscow has vetoed UNSC resolutions over disputed Kashmir in the past to help India keep it a bilateral issue.

In this context, India appears to be following its famed strategy of non-alignment and promoting dialogue to resolve issues.

Michael Kugelman, deputy director at think tank the Wilson Center, says India's stand is not surprising as it's consistent with its past strategy.

He adds that Delhi doesn't "seem comfortable with what is happening in Ukraine but it's not likely to change its stand".

"It simply can't afford to do so at the moment because of its defence and geopolitical needs," he says. Though he adds that Delhi has chosen some strong words in the UNSC to show it's not comfortable with the situation in Ukraine.

India also has the tough task of trying to evacuate 20,000 citizens, mostly students, from Ukraine.

Former Indian diplomat Anil Triguniyat, who served in Moscow and also in Libya where he oversaw the evacuation of Indian citizens when conflict broke out in 2011, says safety assurances are needed from all parties in a conflict to run a successful evacuation operation.

"India can't take a side at the risk of endangering the safety of its citizens. Moreover, it's seeing the holistic picture which involves keeping channels open with everyone," he adds.

In that sense, India is in a unique position as it's one of the few countries which has good relations both with Washington and Moscow.

Indian Prime Minister Narendra Modi has spoken to Russian President Vladimir Putin and Foreign Minister Subrahmanyam Jaishankar has held talks with officials in Washington.

Mr Modi has also held talks with Ukrainian President Volodymyr Zelensky. Mr Triguniyat says India has done well in keeping diplomatic channels open with both sides.

"India hasn't criticised Russia directly but it's not that India has turned a blind eye to the suffering of Ukrainians. It has adopted a balanced approach. It talked strongly about territorial integrity at the UNSC and it was clearly meant to highlight Ukraine's plight," he added.

But if Washington and its European allies continue to impose severe sanctions on Russia, India may find it tough to continue doing business with Moscow.

The US seems to understand India's position at the moment but there are no guarantees it will continue to do so.

When US President Joe Biden was recently asked about India's stand, he didn't give a definitive answer. "We are going to have consultations with India [over Ukraine]. We haven't resolved that fully," he said.

The issue of sanctions over the purchase of the S-400s still loom. The Countering America's Adversaries Through Sanctions Act (Caatsa) was introduced in 2017 to target Russia, Iran and North Korea with economic and political sanctions. It also prohibits any country from signing defence deals with these nations.

Washington had not promised any waiver even before Russia invaded Ukraine, and experts believe that the issue could become a bargaining chip between India and the US.

Meanwhile, Moscow could use its own pressure points which include strengthening ties with India's arch-rival Pakistan if it sees a change in Delhi's strategy.

Russia has accepted India's growing ties with the US in the past two decades but Ukraine is a red line that it wouldn't want Delhi to cross.

Mr Kugelman says such tipping points will only come if the conflict in Ukraine becomes prolonged and ends up creating a bipolar world.

"Let's just hope it doesn't happen. But if it does, India's foreign policy will be severely tested," he says.