The US foreign and defense chiefs have reportedly offered fresh military aid to Ukraine during their first visit to Kyiv since Russia's invasion began in February.

US media quote senior government officials as saying that Secretary of State Antony Blinken and Secretary of Defense Lloyd Austin held talks with Ukrainian President Volodymyr Zelenskyy on Sunday.

The reports say the secretaries announced new military assistance totaling 713 million dollars for Ukraine and neighboring countries.

They reportedly told Zelenskyy that the US embassy in Kyiv will resume operations soon, and that US President Joe Biden will nominate a new ambassador to Ukraine this week.
Embassy officials had temporarily evacuated from the capital. The post of the US ambassador to Kyiv has remained vacant for three years.

Two months into its invasion, Russia recently announced that a "second phase" of its military operations had started. It is stepping up its offensive in eastern Ukraine.

The US announced last week that it is additionally sending 72 Howitzers and more than 140,000 artillery rounds to Ukraine to help prepare for ground battles.

The secretaries' visit and additional aid are taken to indicate the Biden administration's intention to keep Russia in check.

Their trip to Kyiv, reportedly by land from Poland, was kept secret for security reasons.

US media say they were asked to refrain from reporting on the secretaries' visit until they left Ukraine.

Defense Secretary Austin is now scheduled to host a meeting with NATO officials at a US air base in Germany on Tuesday.

The topics are expected to include the latest battlefield assessment of the Russian offensive in Ukraine as well as ways to ensure a continued flow of security assistance.