Turkey's main political parties, including the ruling Justice and Development Party (AK Party), the opposition Republicans' People Party (CHP) and the opposition Nationalist Movement Party (MHP) have released a joint declaration on Sunday which condemns the deadly terrorist attack in Istanbul.

"Our people should feel at ease, the terror groups against all humanity will be defeated, Turkish people will win," the declaration read. "These terrorists will be annihilated or they will be taken to court."

"Regardless of our different political views, we particularly say that we share this pain" the declaration adds and continues, "We say that we will have the same united stance now as how we had against the coup attempt [the July 15 coup attempt]."

Istanbul was rocked by twin blasts late Saturday, which killed 38 people and injured 155 others, 14 of whom are in critical condition. Officials have noted that initial findings suggest the brutal attack was carried out by the PKK terrorist organization.