KABUL, Afghanistan — The Taliban are expected to meet with Afghan opposition leaders in Moscow in the coming days, a development that could further undermine the government of President Ashraf Ghani, which has found itself excluded from the talks seeking an end to the 17-year war.

Even as the insurgents say they are close to a deal on core issues with American diplomats, they have refused to meet with the Afghan government. Mr. Ghani has repeatedly expressed concern that if the Americans rush to make a deal with the Taliban before the insurgents agree to negotiate with his officials, it could undermine a fragile Afghan state built at tremendous cost.

For the Taliban to go around Mr. Ghani to meet with some of the country’s major political leaders, many of whom are at odds with him, would surely further anger the Afghan president.

“At this moment, we do not see the need for such a meeting,” said Sebghat Ahmadi, a spokesman for the Afghan Foreign Ministry. “We know it will not help Afghanistan toward reaching peace at all, so it’s little more than a political drama.”