Kyiv: US secretary of State Antony J Blinken and Defence Secretary Lloyd J. Austin III met with Ukrainian President Volodymyr Zelensky on Sunday, becoming the first senior US officials who have visited Ukraine since Russia launched its military operation in Kyiv on February 24.

"They (Blinken and Austin) are right now in Kyiv, talking to the president," and "maybe something will be decided regarding how they can help," Oleksiy Arestovich, an adviser to President Zelensky confirmed the news during an interview with a Russian lawyer and activist on YouTube.

The US top diplomat and top defence official arrived in Kyiv on Sunday, The New York Times reported.

The US government has always backed Ukraine with financial aid and weapons and also helped in leading the international campaign of sanctions against Russia. But this visit has been called under pressure as recently several European officials including British Prime Minister Boris Johnson, and the PM of Spain and Denmark have visited the country.

US officials did not announce their visit but it was Zelenskyy who revealed it in his speech on Saturday, saying that he would use this meeting to discuss the "military assistance we need."

A few weeks after Russia started its military operation in Ukraine, the prime ministers of Poland, the Czech Republic and Slovenia travelled to Kyiv in March, which was kept under tight wraps, reported The New York Times.

Over the following weeks, they were followed by leaders of Britain, Lithuania, Latvia, Slovakia, Estonia, Spain and Denmark. Ursula von der Leyen, the president of the European Commission, visited both Kyiv and Bucha, where journalists and investigators have found evidence of atrocities.

This is not the first time for America to visit the war zones unannounced, in Iraq and Afghanistan, the visit was typically not announced until after the official had arrived in the country and sometimes not even until after they had left, as reported by The New York Times.

Security concerns and contested airspace have still required leaders to make long journeys to reach Kyiv. The British government said that Johnson, whose visit in early April was unannounced, used several modes of transportation, including a train from eastern Poland.

The White House had ruled out sending Biden, citing not only the risk but Biden's enormous security requirements. Senior cabinet officials such as Blinken and Austin travel with smaller entourages, according to The New York Times.

Meanwhile, on Thursday, the US authorized new military assistance worth USD 800 million for Ukraine.

Notably, Russia launched a "special military operation" in Ukraine on February 24, which the West has termed an unprovoked war. As a result of this, the Western countries have also imposed several crippling sanctions on Moscow.