Foreign tax credit - timing

[ToBlueSkies]

I have some capital gains in India for which I need to file taxes in the US. Since I will pay income taxes in India on this, I was planning to claim a foreign tax credit on my US tax return. I will know the amount of Indian taxes only by end of May (per my accountant there) and my US return is due on Apr 15th, so can I use estimated taxes on my US return? Or is it easier to file a US extension and use the actual Indian taxes paid?

Would appreciate your feedback. Thanks!