The first bulker carrying Ukrainian grain could leave this week from the port of Chernomorsk through a de-mined corridor in the Black Sea, ministers said on Monday.

Chernomorsk will be the first of three ports to be prepared, followed by Odesa and Yuzhny, to begin exporting more than 20m tonnes of grain after a United Nations-brokered deal to alleviate a global food crisis.

“Within a couple of weeks we will be technically ready to carry out exports from all of the three ports,” Yuriy Vaskov, the deputy minister of infrastructure, told reporters. “Within this week, hopefully the first shipments will be sent out.”

Ukrainian ministers were giving an update on preparations for the grain export scheme after Ukraine and Russia signed an agreement on Friday. They said the exports will contribute $1bn a month to Ukrainian national coffers.

Ukraine insisted it will remain in full control of its waters and ports and will be responsible for removing mines along a safe shipping corridor out of the three ports.

The deal amounts to a ceasefire to allow the safe passage of ships carrying grain, but was immediately jeopardised when Moscow launched a rocket attack on Odesa at the weekend. Ukrainian officials said there was little damage and grain stores were unaffected.

Ukrainian president Volodymyr Zelenskyy, pictured with Swedish Prime Minister Magdalena Andersson, criticised the missile attack on Odesa at the weekend. Photo: Ukrainian President’s office

Ministers warned that the initiative would be “put on hold” if “something happens in the Black Sea” and said the safe passage of the first convoys would be key to bringing down insurance premiums, according to Monday’s briefing.

Officials from Ukraine, Russia and Turkey were setting up a joint coordination centre in Istanbul on Monday with responsibility for monitoring the shipping corridor.

The process will ramp up in the coming days, with ports being prepared and commercial shipping applying for permits to collect grain.

Ukrainian officials will inform shippers where to muster within its territorial waters. The authorities will order test runs to ensure the corridors are clear of mines before commercial ships leave port.

“The de-mining would be happening within the corridor that’s needed to export grain,” said infrastructure minister Oleksandr Kubrakov.

He said it would be a complex task, and noted that World War II mines still turn up in the area.

“In our territorial waters and in our ports, everything will be controlled by the armed forces of Ukraine — no representatives of the UN or other countries there,” he said.

Officials said they had been talking to the International Maritime Organization and the insurance industry about ensuring coverage for ships.

“As soon as we go through with the first successful trips of our ships, the markets will react to this, and the insurance tariffs will go down,” said Vaskov.

“This is a market the government is not involved with. We have shipowners who are ready to enter the Ukrainian ports in the next couple of weeks and then leave the ports. What conditions they have with insurance… we have no clue.”