Russian missiles struck the Ukrainian port of Odesa on the Black Sea hours after Moscow and Kyiv inked agreements to resume grain deliveries.

The Ukrainian Ministry of Foreign Affairs condemned Saturday's strike as a "slap in the face" to Turkey and the United Nations, who mediated the agreements.

According to the Ukrainian military's Southern Command, two Russian cruise missiles struck the port's infrastructure, and two more were intercepted by Ukrainian air defenses. It did not detail the damage or whether casualties were caused.

"In less than 24 hours, Russia launched a missile attack on the port of Odessa, breaking its promises and undermining its commitments to the UN and Turkey under the Istanbul agreement," said Oleg Nikolenko, spokesman for the Ukrainian Foreign Ministry. "Should Russia fail to meet its obligations, it will bear sole responsibility for a global food crisis."

Nikolenko characterized the missile strike on the 150th day of Russia's conflict in Ukraine as a "spit in the face" of UN Secretary-General Antonio Guterres and Turkish President Recep Tayyip Erdogan. They made enormous efforts to reach an agreement.

Guterres welcomed the agreements during a Friday signing ceremony in Istanbul as "a beacon of hope, a beacon of possibility, and a beacon of relief in a world that needs it more than ever." The agreements aimed to pave the way for the shipment of millions of tons of Ukrainian grain and certain Russian exports of grain and fertilizer that the war had halted.

In his nightly video address, Ukrainian President Volodymyr Zelensky referred to the accords as "a chance to prevent a global catastrophe – a famine that could lead to political chaos in many countries of the world, especially in the countries that help us."

In addition to the attack on Odesa, Russia's military fired a barrage of missiles at an airbase and a railway station in central Ukraine on Saturday, killing at least three people. At the same time, Ukrainian forces launched rocket attacks on river crossings in a Russian-occupied part in the south.

The attacks on vital infrastructure represented new efforts by the combatants to gain the upper hand in the protracted struggle.

In the central Ukrainian province of Kirovohradska, thirteen Russian missiles struck an airport and a railroad infrastructure. According to Governor Andriy Raikovych, at least one service member and two guards were killed. The regional administration claimed that the strikes near Kirovohrad injured thirteen more persons.

In the southern province of Kherson, which Russian soldiers seized early in the invasion, Ukrainian forces preparing for a possible counteroffensive launched rockets toward Dnieper River bridges to disrupt Russian supplies.

Despite progress on that front, fighting continued unabated in the industrial heartland of eastern Ukraine, the Donbas, as Russian forces attempted to make new gains against stubborn Ukrainian resistance.

Russian troops have fought Ukrainian counterattacks but have generally held their footing in the Kherson region just north of the 2014-annexed Crimean Peninsula.

The Ukrainians blasted the Antonivskyi Bridge over the Dnieper River earlier this week with the US-supplied High Mobility Artillery Rocket System, according to Kirill Stremousov, deputy head of the regional administration designated by Russia in Kherson.

Stremousov told the Russian state news agency Tass that the only other bridge of the Dnieper, the dam of the Kakhovka hydropower plant, was also attacked by rockets launched with U.S.-supplied weapons but suffered no damage.

HIMARS, which can launch GPS-guided rockets at targets up to 80 kilometers (50 miles) away, putting it outside the range of most Russian artillery systems, has considerably improved the Ukrainian attack capabilities.

Stremousov told Tass that Ukrainian soldiers also shelled a car bridge across the Inhulets River in settlement of Darivka. According to him, the bridge immediately east of the regional city of Kherson was hit seven times but remained open to traffic.

Stremousov stated that, unlike the Antonievskyi Bridge, the Darivka Bridge has little strategic significance.

Since April, the Kremlin has focused on seizing the predominantly Russian-speaking Donbas region of eastern Ukraine, where pro-Russia separatists have declared independence.

However, Russian Foreign Minister Sergey Lavrov reiterated on Wednesday that Moscow intends to retain control of other territories taken by its soldiers during the battle.