The UK's international trade secretary has apologised to a court for two breaches of a pledge not to licence exports to Saudi Arabia that could be used in the Yemen conflict.
Ministers promised to stop approving shipments in June after a challenge by campaigners at the Court of Appeal.
Liz Truss said the granting of licences for £435,000 of radio spares and a £200 air cooler for the Royal Saudi Land Forces had been "inadvertent".
An internal inquiry is taking place.
In a letter to the Commons Committees on Arms Export Controls, Ms Truss said routine analysis of statistics found a licence for the air cooler for a Renault Sherpa Light Scout vehicle had been issued just days after the ruling.
And a licence for the export of 260 items of radio spares had been issued in July. To date, the letter said, 180 items from that order - with a value of £261,450 - had been shipped.
Ms Truss said: "I have apologised to the court unreservedly for the error in granting these two licences."
Government lawyers had informed the court of the "breaches of the undertaking given", she added.
She said the internal investigation had been launched to establish whether other licences had been issued against the assurances to the court or Parliament, and to ensure there could be no further breaches.
The court case saw the Campaign Against Arms Trade argue that the UK decision to continue to license military equipment for export to the Gulf state was unlawful.
Under UK export policy, military equipment licences should not be granted if there is a "clear risk" that weapons might be used in a "serious violation of international humanitarian law".
Judges hearing the court case decided existing licences should be reviewed but they would not be immediately suspended.
But Ms Truss's predecessor Liam Fox had given an assurance that the government would not grant further export licences while it considered the ruling.
Responding to the government's apology, the campaign's Andrew Smith said: "We are always being told how rigorous and robust UK arms export controls supposedly are, but this shows that nothing could be further from the truth."