Turkey, Saudi Arabia and Pakistan will sign a joint defence agreement later on Friday, sources in Ankara told Middle East Eye.

The deal, which has been under negotiation since last year, marks a significant new trilateral framework amid a deepening regional crisis following Israeli and US attacks on Iran.

Saudi analysts have previously said that Riyadh could activate the defence pact it currently has with Pakistan should it enter the Iran war.

Friday's proposed deal could have similar implications for Turkey, which is already a US and Nato ally.

However, it is not clear what Friday's deal will include in terms of mutual defence.

The deal is expected to be signed in Mecca, one of Islam’s holiest sites, by the leaders of the three Muslim-majority countries.