KYIV - U.S. Secretary of State Antony Blinken arrived in Kyiv on Tuesday in the first visit to Ukraine by a senior U.S. official since Congress passed a long-delayed $61 billion military aid package for the country last month.

The previously undisclosed trip aims to show U.S. solidarity with Ukraine as it struggles to fend off heavy Russian bombardment on its northeastern border.

Blinken, who arrived in Kyiv by train early on Tuesday morning, hopes to "send a strong signal of reassurance to the Ukrainians who are obviously in a very difficult moment," said a U.S. official who briefed reporters traveling with Blinken on condition of anonymity.

"The Secretary's mission here is really to talk about how our supplemental assistance is going to be executed in a fashion to help shore up their defenses (and) enable them to increasingly take back the initiative on the battlefield," the official said.

Artillery, long-range missiles known as ATACMS and air defense interceptors approved by President Joe Biden on April 24 were already reaching the Ukrainian forces, the official said.

Blinken will reassure Ukrainian officials including President Volodymyr Zelenskiy of enduring U.S. support and deliver a speech focused on Ukraine's future, the official said.

Kyiv has been on the back foot on the battlefield for months as Russian troops have slowly advanced, mainly in the Donetsk region to the south, taking advantage of Ukraine's shortages of troop manpower and artillery shells. Russia's forces hold a significant advantage in manpower and munitions.

On Monday, U.S. National Security Advisor Jake Sullivan said Washington was trying to accelerate "the tempo of the deliveries" of weapons to Ukraine to help it reverse its disadvantage.

"The delay put Ukraine in a hole and we're trying to help them dig out of that hole as rapidly as possible," Sullivan said, adding that a fresh package of weapons was going to be announced this week.

EXPANDING THE FIGHTING

Russia now controls about 18% of Ukraine and has been gaining ground since the failure of Kyiv's 2023 counter-offensive to make serious inroads against Russian troops dug in behind deep minefields.

Moscow's troops entered Ukraine near its second largest city of Kharkiv on Friday, opening a new, northeastern front in a war that has for almost two years been largely fought in the east and south. The advance could draw some of Kyiv's depleted forces away from the east, where Russia has been advancing.

"They (the Russians) are clearly throwing everything they have in the east," said the U.S. official.

Economic and political reforms being undertaken by Kyiv will pave the way for the country to join the European Union and eventually NATO, the official said.

While the U.S.-led defense alliance is not likely to admit Ukraine any time soon, individual members are reaching bilateral security agreements with Kyiv. Talks on a U.S.-Ukraine agreement are "in the final stages" and will conclude ahead of the July NATO summit in Washington, the U.S. official said.

The Group of Seven wealthy nations signed a joint declaration at the NATO summit in Vilnius in July last year committing to establish "long-term security commitments and arrangements" with Ukraine that would be negotiated bilaterally.

Kyiv says the arrangements should contain important and concrete security commitments, but that the agreements would in no way replace its strategic goal of joining NATO. The Western alliance regards any attack launched on one of its 32 members as an attack on all under its Article Five clause.

  - Reuters