GENEVA (AFP) - The humanitarian situation in the southern Ukrainian port of Mariupol is "catastrophic" and it is vital that civilians be evacuated, a senior official from Doctors Without Borders (MSF) warned on Saturday (March 5).

The city, which lies near the border with Russia, has been under siege by Russian forces, and a Saturday ceasefire to allow civilians to leave failed to materialise.

"It is imperative that this humanitarian corridor, which could have been created today but which has not really been put in place following non-respect of the ceasefire, is put in place very quickly to allow the civilian population, women and children, to get out of this city," MSF's emergency coordinator in Ukraine, Ms Laurent Ligozat, told AFP.

"The situation is catastrophic and getting worse day by day," he added.

The strategic city and Azoz sea port is considered a key one for Russia to capture.

"Today, there is no more water; people have huge problems accessing drinking water and this is becoming a crucial issue," said Ms Ligozat.

"There is no more electricity, there is no heating. Food is running out, shops are empty.

"For several days quite simply, there has been nothing coming in or going out of the city."

Russia's Defence Ministry earlier declared the ceasefire - to open a humanitarian corridor to allow the city's 450,000-strong population to begin to leave by bus and private cars.

However, Ukrainian officials then called a delay in the evacuation, saying the Russian side had continued to shell the city and its environs.

Russia later announced "offensive actions" had resumed, each side blaming the other for the failure of the ceasefire.

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