ANKARA – Turkey dispatched its military chief to Moscow on Thursday,

seeking approval for an air campaign in Syria’s Kurdish-controlled Afrin region,

although Damascus warned it could shoot down any Turkish planes in its skies.

Turkey’s foreign minister said the Moscow trip by Chief of Staff Hulusi Akar was part of talks with both Russia and Iran, the two main backers of Syrian President Bashar al-Assad, to allow Turkish planes to take part in an Afrin campaign. The diplomacy was the strongest signal yet that Turkey plans direct military action against territory held by Kurdish militia, potentially opening a new front in Syria’s civil war.