Washington, Mar 5 (IANS): The first phase of Saudi Arabia's long awaited purchase of an advanced US missile defence system has been finalised with the formal awarding of a contract, the media reported on Tuesday.

On Monday, Lockheed Martin was awarded the contract for Phase I "long lead items" of the Terminal High Altitude Area Defence (THAAD) missile defence system, to include early engineering development, test equipment, key personnel and initial training development, CNN quoted a Pentagon statement as saying.

The Defence Department said the first phase of the contract will cost $945,900,000.

The State Department had previously estimated the cost of the entire THAAD sale to be $15 billion.

President Donald Trump included the THAAD purchase in his list of proposed $110 billion in arm sales that he touted during his 2017 meeting with Saudi King Salman bin Abdulaziz Al Saud.

The list was a memorandum of intent to fulfil nearly $110 billion in arms sales over the next 10 years.

However, despite the administration's touting of the agreement, the majority of the $110 billion package was not finalised at the time of it being announced and it has taken months for progress on the sale to be made.

In October 2017, the State Department notified Congress that it had approved the possible sale of the THAAD system to Riyadh, saying that the move "furthers US national security and foreign policy interests, and supports the long-term security of Saudi Arabia and the Gulf region in the face of Iranian and other regional threats".