The Saudi-led coalition fighting in Yemen prevented a UN flight carrying aid agency staff travelling to the Houthi-controlled capital, Sanaa, because three international journalists were also on board, aviation sources said.

The coalition, which intervened in the Yemen conflict in 2015 in support of the internationally recognised government of President Abd-Rabbu Mansour Hadi, controls the airspace over Yemen and can prevent any flights made without prior permission.

Aviation sources said on Tuesday that the flight was prevented from taking off from Djibouti to Sanaa because three BBC journalists were on it.

Confirming the report, the United Nations has demanded media access to report on what it called a "man-made catastrophe".

READ MORE: Yemen's 'unfathomable pain and suffering'

"Steps like this do not help," Farhan Haq, the UN spokesman, told reporters in New York. "This has been a large man-made humanitarian problem, the world needs to know and journalists need to have access."

The coalition claimed the journalists' security could not be guaranteed in rebel-controlled areas, according to the UN Office for the Coordination of Humanitarian Affairs (OCHA) in Yemen.

They were instead advised to travel on commercial flights, a spokesman for OCHA said.

Hakim Almasmari, editor-in-chief of the Yemen Post, said the media should be able to cover the "massacre" and the viewers allowed to judge who is wrong or right.

"It’s very sad to see that there’s no international pressure from the UN and world leaders," he told Al Jazeera, from Sanaa.

A source in the coalition said that the Yemeni government was the only party entitled to issue visas for foreigners and that entry must be made via commercial flights through Aden airport, which is under its control.

"The United Nations is not concerned with transporting journalists, except those who are coming to cover its own activities," a source in the coalition told Reuters news agency, adding that the UN must ensure the journalists' safety and make sure they do not carry out any other activity.

The impoverished Arab country has been engulfed in a civil war since September 2014 that has killed more than 10,000 people and displaced more than 3 million.

"The lack of coverage is also hindering humanitarians' effort to draw the attention of the international community and donors to the humanitarian catastrophe the country is experiencing," Ben Lassoued said.