Turkey's top diplomat stressed Monday the regional defence pact with Pakistan and Saudi Arabia was not aimed at any particular country and open to others, including Egypt.

Foreign Minister Hakan Fidan's remarks came after the first ministerial meeting of the Mecca Joint Defence Agreement which commits Turkey, Pakistan and Saudi Arabia to mutual defence in the event of any of them being attacked.

"This alliance is founded on international principles such as respect for the sovereignty and territorial integrity of states and non-interference in their internal affairs," he told reporters in Istanbul after they met in an Ottoman-era palace.

"The alliance is not against any state and is open to all states in our region that adhere to these fundamental principles," he said of a pact inked against a backdrop of war between the US and Iran, and regional attacks by Tehran-backed Houthi rebels.

It unites NATO's second-largest army, Turkey, with the Islamic world's only nuclear-armed state, Pakistan, and the leading Gulf power in Saudi Arabia.

The meeting came as Israel on Monday said it signed a three-billion euro deal with Athens (almost $3.5 billion) to set up the "Achilles Shield" aerial defence system for Greece.

Pakistan's Foreign Minister Ishaq Dar and his Saudi counterpart Prince Faisal bin Farhan were also at the talks, alongside defence ministers from all three countries and their military chiefs of staff.

- 'Not someone to be taken seriously'-

Asked if other countries including Egypt could join the pact, Fidan said it was "indeed possible" but stressed consultations were ongoing to determine conditions, procedures and standards for membership.

"We are also working on a roadmap regarding the processes of joining the alliance," he added.

Asked about Israel's increasingly bellicose rhetoric towards Turkey, Fidan noted the proximity of the upcoming Israeli elections and said that Prime Minister Benjamin Netanyahu was "not someone to be taken seriously".

Earlier this month, Turkey said it was seeking an international arrest warrant for Netanyahu accusing him of "genocide" linked to Israel's interception of a Gaza-bound aid flotilla, prompting a flurry of verbal exchanges between the two nations.

"The main audience Netanyahu must answer to is the international community, because Netanyahu, his mentality, and the genocidal crowd acting with him constitute a threat, not only for Turkey but for global security as a whole," Fidan said.