The number of attacks on Ukrainian Armed Forces positions and populated areas of the Donbass seen over the past week was the highest yet in the past six months, Interfax reported National Security and Defense Council of Ukraine (NSDC) Secretary Oleksandr Turchynov as saying while visiting Ukrainian positions in the zone of operation of the Joint Forces.

"Artillery weapons, tanks, and rocket launchers prohibited by the Minsk Agreements are being used," Turchynov said according to the NSDC press service.

According to the secretary, Ukrainian territory was shelled up to 30 kilometres deep, which inflicted damage on civilian infrastructure and caused military and civilian casualties.

Kaljulaid had visited the conflict region on Thursday. "The entire day yesterday was spent on visiting Eastern Ukraine," she wrote on social media on Friday. "This is a place where war is going on in the middle of Europe. This is Europe's largest humanitarian catastrophe. And there are people living there who, day after day, need to cope with all this."

According to her statement, the president on Thursday visited Majorsk Control Point, the village and refugee centre of Chasiv Yar, an area of the city of Sloviansk, the city of Kramatorsk and a refugee centre established there.

Kaljulaid first world leader to visit conflict zone

Prior to her tour of the conflict zone of Eastern Ukraine, Kaljulaid said that she wanted to visit the region to see the activity there for herself. The Estonian head of state on Tuesday stressed that the world cannot get used to war and occupation in Ukraine, or consider it inevitable.

On a three-day visit to Ukraine, Kaljulaid met with President Petro Poroshenko, Prime Minister Volodymyr Groysman, Deputy Prime Minister Ivanna Klympush-Tsintsadze and Chairperson of the Verkhovna Rada Andriy Parubiy. She also opened a business seminar in Kiev, met with local entrepreneurs and civil society representatives.

The Estonian president also visited Eastern Ukraine, where she met with the governor of the Kharkiv region and reviewed renovation work being done in war-damaged areas as well as the humanitarian situation. Kaljulaid also visited the Joint Forces Operation Headquarters in Eastern Ukraine.

On Thursday, Kaljulaid made history as the first foreign leader to visit the conflict zone in Eastern Ukraine, where she met with local authorities and heads of the Ukrainian Armed Forces and spoke with soldiers and local residents as well as employees of humanitarian aid organisations.