Syria's main Western-backed opposition group says it will not attend the next round of peace talks in Moscow on the Syrian conflict.

The Syrian National Coalition's representative to the U.N., Najib Ghadbian, told reporters Wednesday that his group had been invited to the second round of Moscow talks set for April 6 through April 9.

The coalition also boycotted the first round of talks in Moscow in January, along with most rebel groups.

Ghadbian rejects the idea of Russia framing the talks as a dialogue with the Syrian government. The coalition insists that President Bashar Assad must go.

Russia is a key ally of Assad's government, but its U.N. ambassador on Tuesday said it's time for a "breakthrough in a political settlement" in the four-year conflict.