Confusion in dates

Ambiguity over the effective dates for the new Afghanistan-Pakistan Transit Trade Agreement (APTTA) was cleared at the joint press conference by Prime Minister Gilani and Afghan President Karzai and "The Islamabad Declaration" signed by the two countries.
"You are aware that the new Afghanistan-Pakistan Transit Trade Agreement came into force yesterday (June 10) is indeed an important development", said the prime minister while addressing the joint press conference on Saturday. While in the Islamabad Declaration, signed by Minister of State for Foreign Affairs Hina Rabbani Khar and Afghan Foreign Minister Dr Zalmai Rassoul on behalf of their respective countries, welcomed the operation of APTTA on 12 June 2011 and agreed to continue to take all necessary steps to ensure that this Agreement was fully implemented.