Taiwan’s parliament authorised the government ​on Friday to sign US agreements for four arms sales packages, after officials warned that Taipei ‌would go to the back of the queue if it missed the deadline, sending the wrong message to Washington.

The back and forth on Taiwan’s defence spending has provoked concern in the United States, as it is the most important international backer and arms ​supplier of the Chinese-claimed island, despite a lack of formal diplomatic ties.

“This body upholds the principle of ​placing national security first and firmly defending territorial integrity,” parliament speaker Han Kuo-yu said, ⁠reading the resolution which passed unanimously.

He urged the government to submit a complete report on the weapons delivery ​schedule for parliament to review after it signs the letters.

The weapons covered include TOW anti-tank missiles, M109A7 self-propelled howitzers, ​Lockheed Martin-made Javelin missiles and the HIMARS multiple launch rocket system.

President Lai Ching-te’s government has tried to get parliament to pass $40 billion in extra defence spending but the opposition, which controls the most seats, says the proposals are unclear, and it cannot ​be expected to pass “blank cheques”.

Both opposition parties drew up their own, cheaper alternatives, but the defence ministry said ​the letters of offer and acceptance for the weapons have to be signed with the United States by Sunday, or Taiwan ‌risked losing ⁠its place in the production and delivery queue.

Parliament’s formal authorisation on Friday came a day after lawmakers of both sides agreed that the government could sign the deals in advance, even if spending reviews were not approved in time.

Taiwan’s defence ministry expressed its thanks for the authorisation, rejecting opposition claims the plans were opaque.

They were ​prepared through a “rigorous project approval ​process” it added, to ⁠meet the military’s requirements.

Ruling party lawmakers welcomed the approval.

“The advance authorisation to sign before the budget is reviewed is intended to ensure that Taiwan’s acquisition of these important ​systems is not delayed or cancelled,” said Wang Ting-yu, a Democratic Progressive Party lawmaker ​who sits ⁠on parliament’s defence committee.

On Tuesday, Defence Minister Wellington Koo told reporters the letters of offer and acceptance for 82 HIMARS systems the U.S. announced as part of an $11-billion arms sale package for Taiwan would expire on March 26.

The Trump ⁠administration has ​pressed allies to boost defence spending, a plank Lai’s government has embraced as ​China steps up drills and exercises around the island to press its sovereignty claims.

Taiwan rejects Beijing’s claims, saying only its people have the ​right to decide the island’s future.