The fresh Turkish deployment came as, Turkish and Russian delegations met in Ankara, to discuss steps to de-escalate tensions in Idlib.
This is the last major enclave of opposition to President Bashar al-Assad. Turkish President has threatened to repel the Russian-backed Syrian forces unless they withdraw from the region by the end of the month.
Despite the build-up of Turkish troops, Syrian government forces have pressed their advances.
Syrian Observatory for Human Rights, said that around 430 Turkish military vehicles had crossed into Idlib, while one battalion of soldiers have been sent to each of the 12 observation posts in Syria.