"The use of radical elements hostile to the Islamic Republic shows that the Americans are trying to increase the pressure against Iran," said Alaeddin Boroujerdi, chairman of the Iranian parliament's foreign affairs committee.

His comments, carried by the semi-official ISNA news agency, were the first reaction by a senior Iranian official to Trump's appointment of conservative firebrand John Bolton as his national security chief.

That came days after Trump picked hardliner Mike Pompeo as his top diplomat.

The appointments raised fears of US military action against Iran.

Bolton, a former UN ambassador and outspoken supporter of the US-led invasion of Iraq in 2003, opposes a historic 2015 Iran nuclear deal which Trump has threatened to scrap.

Bolton has also championed regime change in Tehran, writing in a 2015 op-ed that "only military action ... can accomplish what is required".

Boroujerdi said that Trump was working "to reassure the Zionists (Israel) and Saudi Arabia".

"We need to strengthen our relations with important countries like China and Russia, which are also subject to US sanctions and face significant challenges from that country," he said.

Boroujerdi said boosting ties with China and Russia, permanent members of the UN Security Council, would "help reduce the impact of US pressure".

Iran has in recent years developed its relations with China and Russia.

Tehran and Moscow are key backers of Syrian President Bashar Al-Assad, while China is Iran's top trading partner.