Questions have once again been raised over US President Donald Trump’s grasp on foreign policy after he appeared to misunderstand the role played by Lebanese militant organisation Hezbollah in the Middle East’s complex geopolitics.

During a news conference with Lebanese President Saad al-Hariri in the White House’s Rose Garden on Tuesday, Mr Trump was asked about his position on the Shia group.

“The prime minister and I have just concluded an extensive conversation about the challenges and opportunities facing Lebanon and its neighbours,” Trump said.

Hezbollah warns Isis is a great danger

Hezbollah was a “menace” from within to the Lebanese people and the region, Mr Trump added.

“Lebanon is on the front lines in the fight against Isis, al-Qaeda and Hezbollah. The Lebanese people, of all faiths, are working together to keep - and you know this, and we've been discussing this at great length - their country safe and prosperous.”

While the US has condemned Hezbollah as a terrorist group, and Congress is considering stepping up sanctions, its political wing is the most powerful entity in Lebanon’s deeply divided coalition government.

The response was met with silence from Sunni Prime Minister Hariri, for whom Hezbollah is a de facto power sharing partner under the Lebanese constitution, which guarantees Shia, Sunni and Christian representation at the highest levels of government.

Hezbollah itself is engaged in fighting Isis both in the north of Lebanon and over the border in Syria, where it is allied with Syrian President Bashar al-Assad, and receives extensive financial and military backing from Iran.

In response to a follow up question about the US’ position on Hezbollah, Mr Trump said he would clarify his position “in the next 24 hours”.

Hezbollah’s war in Syria threatens to engulf Lebanon Show all 2 1 /2 Hezbollah’s war in Syria threatens to engulf Lebanon Hezbollah’s war in Syria threatens to engulf Lebanon nasrallah.jpg Lebanese Hezbollah supporters listen to the televised speech of the movement's chief Hassan Nasrallah in Mashghara in the western Bekaa Valley on May 25, 2013 Getty Images Hezbollah’s war in Syria threatens to engulf Lebanon hezbollah-rocket.jpg A image grab taken from a video uploaded on Youtube on May 24, 2013, shows smoke billowing from buildings in the city of Qusayr, in Syria's central Homs province, following an alleged missile strike by Hezbollah Getty Images

Speaking to reporters later in the day, Mr Hariri was careful to sidestep questions about whether the president did not understand Hezbollah’s function within the Lebanese state and outside it.

He also said he had spoken at length to Mr Trump about how sanctioning banks which do business with the group could harm the Lebanese banking industry in general.

The Lebanese premier was visiting Washington DC to lobby for more economic support for the tiny country, which is struggling to cope with an estimated 1.5 million Syrian refugees - equivalent to one in four of the population.

The State Department has pledged an additional $140 million (£108 million) to assist with the crisis.

Mr Trump also promised continued American military help to prevent Isis and other militant groups from gaining a foothold in the country.