Top foreign policy experts have warned US President Barack Obama that his Yemen policy, steeled by lethal drone strikes on terror suspects, is not sustainable and could harm long-term US security.

In a letter fanning debate on US policy towards a hot front in the campaign against Al Qaeda, the experts said on Wednesday that Yemenis perceived America as almost purely concerned with ruthless anti-terrorism operations.

The Obama administration pushed back strongly, highlighting a recently announced new $ 52 million aid increase to tackle Yemen’s humanitarian crisis and insisted the US approach towards the country was “balanced.”

“We believe the current US strategy jeopardises our long-term national security goals,” said the letter, signed by 27 bipartisan experts under the auspices of the Atlantic Council and the Project on Middle East Democracy.

A strategy that emphasises economic and political concerns would better serve Yemeni stability and US interests, “rather than a primary focus on counterterrorism efforts and direct military involvement,” the letter said.

“We accept that the US will take action against those who plot attacks against Americans when there is actionable intelligence,” the experts said.

“However, removing members of militant groups with targeted strikes is not a sustainable solution and does not address the underlying causes that have propelled such forces to find fertile ground in Yemen.”

Washington was a key player in a political transition that saw president Ali Abdullah Saleh step down this year after an Arab Spring-inspired uprising, ceding power to the current President Abdrabuh Mansur Hadi.

Yemen, the base of Al-Qaeda in the Arabian Peninsula (AQAP) was the locus of several thwarted terror plots against American targets, including a bid to bring down a US airliner over Detroit on Christmas Day 2009.

Yemeni Foreign Minister Abu Bakr Al Kurbi told media on Wednesday that the Sanaa government had asked in some cases for drone strikes to target Qaeda leaders, lifting the veil on US attacks.

Obama said at the Nato summit in Chicago last month he was “very concerned” about Qaeda in Yemen, after an AQAP suicide bomber killed 100 Yemeni troops.