The US Senate approved an amendment to a key defence spending bill which threatens to derail a Department of Commerce (DoC) deal to lift trade sanctions against ZTE.

Senators voted to include an amendment to the wide-reaching Defence Bill, which would overturn the rescue package and reinstate a block on US companies selling components to ZTE.

The Defence Bill, including the amendment on ZTE, will now go to the House of Representatives (HoR), which already passed a version of the proposed legislation without the ban on ZTE included.

Both versions of the bill must be reconciled, if necessary through negotiations between the Senate and the HoR, to form a consistent Congress version of the bill which then goes to the President for final sign-off.

President Trump can veto the Congress bill, however given enough support from both chambers his veto can be overruled and the bill becomes law anyway.

It remains unclear how far the row into continuing sanctions on ZTE will go as Trump played a strong part in negotiations to save the vendor.

However, the uncertainty will do little to help the Chinese vendor, which suffered another hit to its share price with the latest revelations. ZTE’s shares on the Hong Kong stock exchange dipped 24 per cent for the day by 4pm local time (19 June), with shares listed in Shenzhen down 10 per cent in the same period.

Prior to developments from the US senate, the situation had begun to settle. ZTE agreed to pay a $1 billion fine and other measures demanded by US authorities. It had also recommenced trading on its shares and resumed business operations suspended in May when it was slapped with the damaging sanctions.