BAKU, May 31 (Reuters) - British oil company BP BP.L expects to sign a contract at the end of June extending its production sharing deal for Azerbaijan's biggest oilfields until 2050, the company's regional head said on Wednesday.

The existing deal is due to expire in 2024 and BP-led consortium and Azeri state oil firm SOCAR signed a letter of intent in December to continue developing the giant Azeri-Chirag-Guneshly (ACG) offshore fields until 2050.

"End of June is a very reasonable time for it," Gary Jones, BP's regional head for Azerbaijan, Georgia and Turkey, told reporters when asked when the contract was due to be signed. "It's a big deal. We want to get it right."

The shareholders in the consortium include BP, SOCAR, Chevron CVX.N , INPEX 1605.T , Statoil STL.OL , ExxonMobil XOM.N , TPAO, ITOCHU 8001.T and ONGC Videsh ONVI.BO .

Azeri President Ilham Aliyev said on Wednesday he expected the contract to be signed soon.

"We are thinking about development of the ACG bloc and I think we will reach a final agreement with investors," Aliyev said at the annual Caspian Oil & Gas conference in Baku.

BP came under fire from Aliyev earlier this decade when the country's leader criticised the oil firm for lower than promised output levels. Oil output at ACG totalled more than 7.1 million tonnes in the first quarter of this year.

(Reporting by Nailia Bagirova; writing by Margarita Antidze; editing by David Clarke) ((margarita.antidze@thomsonreuters.com; +995322999370; Reuters Messaging: margarita.antidze.thomsonreuters.com@reuters.net))