South Korean President Yoon Suk Yeol on Tuesday ordered the government to quickly send rescue workers and medical supplies to quake-hit Turkey, his office said.
Yoon's instruction came a day after a 7.8 magnitude earthquake struck Turkey and Syria, killing more than 4,300 people in the two neighbouring nations.
"President Yoon Suk Yeol this morning ordered the dispatch of rescue personnel using military aircraft to assist Turkey with the damage from the earthquake, and to swiftly move to send emergency medicine and medical supplies," Yonhap News Agency quoted his office as saying.
Meanwhile, Sputnik and Reuters reported a second quake on Tuesday morning, saying the European Mediterranean Seismological Center registered a magnitude 5.6 earthquake in central Turkey.
The earthquake occurred at a depth of two kilometres, 5 kilometres from the Golbasi area.
Yoon described Turkey as a "brother nation that immediately sent troops without hesitating following the Communist invasion in 1950", she said.
Turkey fought alongside South Korea in the 1950-53 Korean War.
The presidential office said Yoon instructed the government to cooperate closely with the Turkish authorities through the foreign ministry and South Korea's diplomatic missions in the country.
Yoon extended his condolences in an early morning tweet on Tuesday, saying: "My heart goes out to the people of Turkey and Syria during this difficult time. Korea sends our deepest condolences to those who have lost their loved ones. We stand ready to assist Turkey, a brotherhood forged in blood during the Korean War, in any way possible."
Other offers of assistance came from countries across the world. Here are some of the chief pledges of support.
European Union
The European Union has mobilised 10 search and rescue teams for Turkey after the stricken country requested EU assistance, EU foreign policy chief Josep Borrell and EU crisis management commissioner Janez Lenarcic said.
The EU's Copernicus satellite system has been activated to provide emergency mapping services, it said adding the bloc was ready to support those affected in Syria too.
United Nations
The UN General Assembly observed a minute of silence in tribute to the victims.
"Our teams are on the ground assessing the needs and providing assistance. We count on the international community to help the thousands of families hit by this disaster, many of whom were already in dire need of humanitarian aid in areas where access is a challenge," UN Secretary-General Antonio Guterres said.
India
Two of India's National Disaster Response Force teams comprising 100 personnel with dog squads and equipment were ready to be flown to the affected area, the foreign ministry said. Doctors and paramedics with medicines were also being readied.
Prime Minister Narendra Modi said he was "anguished" and "deeply pained" by the deaths in Turkey -- with whom India has frosty relations -- and Syria.
United States
US President Joe Biden said he was "deeply saddened" by the loss of life. US teams were "deploying quickly to begin to support Turkish search and rescue efforts", he added.
National security spokesman John Kirby said the United States was sending two search-and-rescue teams of 79 people each, while the Pentagon and USAID were coordinating with their Turkish counterparts.
Germany
Germany, home to about three million people of Turkish origin - will "mobilise all the assistance we can activate", Interior Minister Nancy Faeser said.
Germany's Federal Agency for Technical Relief "can set up camps to provide shelter as well as water treatment units", she said. Generators, tents and blankets are also being readied.
Russia
President Vladimir Putin promised to send Russian teams to both countries in telephone calls with Syria's Bashar al-Assad and Turkey's Recep Tayyip Erdogan.
"In the nearest hours, rescuers from the Russian emergency ministry will take off for Syria," the Kremlin said. The defence ministry said 300 military personnel deployed in Syria were helping with the clear-up effort.
Ukraine
Ukrainian President Volodymyr Zelensky said that his war-torn country was "ready to provide the necessary assistance to overcome the consequences of the disaster."
Greece
Kyriakos Mitsotakis, prime minister of Turkey's historic rival Greece, whose relations with Ankara have suffered from a spate of border and cultural disputes, pledged to make "every force available" to aid its neighbour.
Athens is sending rescuers and supplies on a military plane.
Israel
Israel's Prime Minister Benjamin Netanyahu said he had approved the sending of aid to Syria -- whose government does not recognise Israel -- after receiving a request through diplomatic channels.
The government will also send humanitarian assistance to Turkey, he said.
However, a Damascus official denied they had requested help in the first place.
NATO
NATO chief Jens Stoltenberg voiced "full solidarity" with ally Turkey, saying he was in touch with Turkey's top leadership and "NATO allies are mobilising support now".
Sweden
Prime Minister Ulf Kristersson of Sweden, whose bid to join NATO is meeting Turkish resistance, sent his "deepest condolences" to Erdogan. "We stand ready to offer our support," Kristersson tweeted.
Poland
Polish firefighters flew from Warsaw to the Turkish city of Gaziantep. "Our team will be working non-stop, 24 hours a day, in two locations," said Andrzej Bartkowiak, chief commandant of the state fire service.
Gulf states
Qatar said it would send 120 rescue workers to Turkey, alongside "a field hospital, relief aid, tents and winter supplies".
Emirati President Sheikh Mohamed bin Zayed Al-Nahyan offered "assistance" in telephone calls with his Syrian and Turkish counterparts, the official WAM news agency reported.
Canada
Prime Minister Justin Trudeau tweeted: "our hearts go out to those who lost loved ones. Canada stands ready to provide assistance."
France
President Emmanuel Macron said France stood ready to provide emergency aid to Turkey and Syria. "Our thoughts are with the bereaved families," he tweeted.
Britain
Foreign minister James Cleverly said the UK was sending a team of 76 search and rescue specialists, equipment and rescue dogs. Britain was also sending an emergency medical team to assess the situation on the ground.
Japan
The government in Japan -- which frequently suffers earthquakes -- is dispatching the Japan Disaster Relief Rescue Team to Turkey.
Iran
Iran is ready to provide "immediate relief aid to these two friendly nations", President Ebrahim Raisi said, offering condolences on the "heartbreaking incident".
Italy
Italy is sending support from its civil protection department. Rome said other flights would follow with medical personnel and equipment.
United Arab Emirates
The United Arab Emirates pledged humanitarian assistance worth around $13.6 million to Syria, including search and rescue teams, urgent relief supplies and emergency aid.
Official news agency WAM said the UAE had already dispatched a first plane to southern Turkey, where it is planning to establish a field hospital.
IANS and AFP