The dates of U.S. Secretary of State John Kerry's visit to Kyiv have yet to be agreed upon, Ukrainian deputy presidential chief of staff Kostiantyn Yeliseyev has said.

"No, there is no date yet. But, as we see, our relations are developing very dynamically on all levels. Therefore, the date, which is being actively coordinated through diplomatic channels now, is only a matter of time," Yeliseyev said in an interview with Interfax-Ukraine.

Kerry promised to visit Ukraine during meetings with Ukrainian President Petro Poroshenko on the sidelines of a nuclear security summit in Washington in early April, he said.

"The matter concerns the importance of launching a bilateral dialogue mechanism, active work of the Ukrainian-U.S. strategic commission under Kerry's and Ukrainian Foreign Minister Pavlo Klimkin's leadership, and more active security and defense cooperation," Yeliseyev said.

Ukraine also expects to sign a document with the U.S. on extending $1 billion in loan guarantees, Yeliseyev said.

"We are also starting a dialogue with the U.S. in the context of forming a new U.S. budget for next year, so that it should increase the U.S. financial assistance for strengthening Ukraine's defense," he said.