CAIRO, Feb. 21 (Xinhua) -- Iran on Saturday vowed to uphold national unity and designated the naval and air forces of European Union (EU) states as terrorist organizations. The move came as a U.S. envoy's controversial remarks drew widespread condemnation across Arab countries.

Speaking at a meeting in Tehran, Iranian President Masoud Pezeshkian reaffirmed his administration's commitment to national resilience and unity, saying that Iran will not yield to external pressure as it navigates nuclear negotiations with the United States.

"We will make efforts and will not bow before any of the difficulties we are faced with," he said in remarks carried live by state-run IRIB TV.

While acknowledging difficulties, Pezeshkian called for national cohesion, urging Iranians to "put aside the differences" and stay united.

Pezeshkian's remarks follow a recent U.S. military buildup in the Middle East and two rounds of indirect nuclear talks between Washington and Tehran, which have centered on Iran's nuclear program and the possible lifting of U.S. sanctions.

Meanwhile, Iranian Foreign Ministry said the country had designated the navies and air forces of all member states of the EU as terrorist organizations.

The move is to respond to the EU's recent "unlawful and unjustified" decision to label Iran's Islamic Revolution Guards Corps as a terrorist organization, the ministry said in a statement.

The EU decision is "in contradiction with the fundamental principles and rules of the United Nations Charter and international law," the statement said.

Against tense regional developments, U.S. Ambassador to Israel Mike Huckabee said in a Friday interview that Israel has a "biblical right" to claim control over the entire Middle East, or at least most of the region.

The comments drew condemnation across the Arab countries as the Arab League called them "highly extremist."

Huckabee's remarks, being illogical and irrational, are "inconsistent with the fundamental principles and established norms of diplomacy," Secretary-General of the Arab League Ahmed Aboul-Gheit said in a statement.

Those remarks "serve only to inflame sentiments and stir religious and national emotions" when countries are exploring ways to implement the Gaza ceasefire and "seize the opportunity to launch a serious political process towards peace," he said.

Egyptian Foreign Ministry expressed its "astonishment" over the remarks on Saturday, describing them as a "blatant violation" of international law and the United Nations Charter.

Also calling the rhetoric "extremist," Saudi Foreign Minister Faisal bin Farhan Al Saud said the same day that Huckabee's action "portends grave consequences and threatens international peace and security by antagonizing the countries and peoples of the region and undermining the foundations of the international order."