US Undersecretary of State Wendy Sherman visiting Warsaw on Monday tried to reassure Poland over recent changes in a European missile defense system.

US Secretary of Defense Chuck Hagel told press on Friday that the United Stated was abandoning the final (fourth) stage of its Eastern European missile defense plan with the focus shifted to perceived threats from Iran and North Korea. As a result of this change deployment of several ballistic missile interceptors in Poland will be scrapped.

However, the third missile shield construction phase in Poland is not endangered, Sherman said in Warsaw and shorter-range interceptors would still be based in Poland as part of NATO’s missile defense system in Europe.

She added that Poland knew about changes in the fourth phase before their announcement.

The Obama administration has planned to put medium-range interceptors in Redzikowo, in northern Poland, starting in 2018, as part of the NATO system. They are meant to protect Europe from attacks from Iran.

Sherman said the Polish site “will go forward as scheduled.”