IRDC.IR: The provisional government and the prime minister Mahdi Bazargan showed interest in having relationships with US after they came to power. Americans were also willing to do so, and despite the whole country were chanting "Down with USA", they started a secret relationship from the very beginning.
Cyrus Vance (US foreign minister during Carter's presidency) notes in his diaries: "After Bakhtiar escaped the country, the most important issue for Washington was if the provisional government was going to keep the relationship between Iran and US.
On February 12th, we sent orders to our ambassador (William) Sullivan, to stay in touch with the provisional government until the time Carter makes his decision about the relationships between the two countries.
We had two immediate priorities:
1. Prevent the unfriendly from reaching out to sensitive intelligence and military equipment.
2. Health and safety of US citizens living in Iran.
Sullivan and US military advisors worked with the provisional government and the military to protect sensitive equipment and facilities. Bazargan's government showing interest in cooperation, was the the sign of the moderates' eagerness to keep the military relations with US, and their anxiety about Iran's foreign security."
HARD Choice (critical years in America`s Foreign policy) - By: Cyrus Vance
Translated by: Roya Jalali