Iran on Saturday launched a research satellite into orbit with a rocket built by the Revolutionary Guards, state media reported.

The launch comes as the United States and European countries accuse Iran of transferring ballistic missiles to Russia that would be likely used in its war with Ukraine within weeks. Iran has denied this, Reuters reported.

The Chamran-1 satellite, which was launched into space by the Qaem-100 satellite carrier, was put into a 550-kilometre (340-mile) orbit and its first signals had been received, the media said, adding that the solid fuel carrier was designed and built by the Aerospace Force of the Revolutionary Guards.

The primary mission of the satellite, which weighs 60 kg (132 pounds), "is to test hardware and software systems for demonstrating orbital manoeuvring technology in height and phase," according to state media.

In January, Iranian media reported that the Sorayya satellite had been launched into a 750 km orbit, the highest by the country so far.

The U.S. military alleges the long-range ballistic technology used to put satellites into orbit could also allow Tehran to launch long-range weapons, possibly including nuclear warheads.

Tehran denies its satellite activities are a cover for ballistic missile development and says it has never pursued the development of nuclear weapons.

Chamran-1's other mission was to "evaluate the cold gas propulsion subsystem in space systems and the performance of the navigation and attitude control subsystems", state media reported.

Iran, which has one of the biggest missile programmes in the Middle East, has suffered several failed satellite launches in recent years due to technical issues.

The U.S. State Department on Thursday imposed sanctions on a Chinese research institute and several companies it said have been involved in supplying Pakistan's ballistic missile program.

Washington similarly targeted three China-based companies with sanctions in October 2023 for supplying missile-applicable items to Pakistan, Reuters reported.

Department spokesperson Matthew Miller said in a statement that the Beijing Research Institute of Automation for Machine Building Industry had worked with Pakistan to procure equipment for testing rocket motors for the Shaheen-3 and Ababeel systems and potentially for larger systems.

The sanctions also targeted China-based firms Hubei Huachangda Intelligent Equipment Co, Universal Enterprise, and Xi'an Longde Technology Development Co, alongside Pakistan-based Innovative Equipment and a Chinese national, for knowingly transferring equipment under missile technology restrictions, Miller said.

"As today’s actions demonstrate, the United States will continue to act against proliferation and associated procurement activities of concern, wherever they occur," Miller said.

Liu Pengyu, spokesperson for China's embassy in Washington, said: "China firmly opposes unilateral sanctions and long-arm jurisdiction that have no basis in international law or authorization of the UN Security Council."

China will "firmly protect" Chinese companies' and individuals' rights and interests, Liu said.

Pakistan's embassy did not immediately respond to a request for comment.

Unidentified assailants opened fire on a polio vaccination team in northwestern Pakistan on Wednesday, killing one of those handing out doses and one policeman escorting him, police said.

The attack in the region bordering Afghanistan comes two days after Pakistan launched its latest national campaign to stamp out the virus, which still poses a health threat in the South Asian nation, although mostly eradicated elsewhere, Reuters reported.

"Unidentified armed men opened fire on polio vaccination team in a subdivision of Bajaur tribal district as they were on the vaccination campaign," district police officer Waqas Rafique told Reuters.

No group has claimed responsibility, but previously Islamist militant groups in the region have claimed similar attacks on polio teams, falsely portraying the inoculation campaigns as a Western conspiracy to sterilise children.

Pakistan began its latest national campaign earlier this week, aiming to administer the vaccine to up to 30 million children, the prime minister's office said.

Pakistan and Afghanistan are the only two countries in the world still struggling to eradicate polio, read the report.

A local police union group called for a strike by policemen and a boycott of security duties for the vaccination campaign in the Bajaur district following the killing of their colleague.