ISLAMABAD- Pakistani Prime Minister Nawaz Sharif today called for a joint session of parliament to consider whether to join the Saudi-led military campaign in Yemen.

For six days, a Saudi-led coalition has bombed Iran-allied Houthi fighters and army units fighting against Yemeni President Abd-Rabbu Mansour Hadi, whose last bastion in the southern city of Aden was heavily shelled overnight.

"Given the close historical cultural and religious affinities between Pakistan and Saudi Arabia, it was reaffirmed that any isolation of Saudi Arabia's territorial integrity will evoke a strong response from Pakistan," the prime minister 's office said in a statement.

"The prime minister further emphasized that all decisions in the matter will be taken in accordance with the wishes of the people of Pakistan. To this end, the prime minister is advising the president to convene a joint session of parliament on Monday April 6 to discuss this matter of national importance."

The statement came after Sharif was briefed by a high-level defence delegation which returned from Saudi on Wednesday.

Largely Sunni Muslim Pakistan is a regional ally of Saudi Arabia, the Gulf's main Sunni Muslim power. Pakistan also shares a long border with Iran, considered to be the centre of Shi'ite power and Saudi's main regional rival. An estimated 20 percent of Pakistanis are Shi'ite.

A senior Pakistani government official told Reuters on Monday that Islamabad would send troops to Saudi Arabia to provide military support to the Saudi-led coalition. But Defence Minister Khawaj Asif denied any decision had been made.

Right-wing religious groups in Pakistan demonstrated last week, vowing to defend Saudi Arabia. But some civil society groups and opposition politicians spoke against intervention, taking the view it could further inflame domestic sectarian tension.

Sharif has long enjoyed close relations with the Saudi royal family. After his second term as prime minister was ended by a military coup in 1999, he was sent into exile in Saudi Arabia.

Saudi Arabia lent $1.5 billion to Pakistan last year to help Islamabad shore up foreign exchange reserves. Pakistani officials initially refused to divulge the source of the loan.