The Prime Minister Theresa May has suffered yet another ministerial resignation, this time while she was in Buenos Aires selling her Brexit deal to world leaders gathered for the G20 summit.

Sam Gyimah, who has resigned as universities and science minister, is overall the 10th minister to quit and the seventh since May concluded her Brexit withdrawal deal that she now appears to have little chance of getting through parliament in the “meaningful vote” on December 11.

Gyimah’s resignation following that of four Asians — the Indian Shailesh Vara, two Sri Lankans, Suella Braverman and Ranil Jayawardena, and a Pakistani, Rehman Chishti — leaves May’s government looking whiter than white.

It is true the Asians are not very well known to the public. In fact, the current Private Eye has a joke about the lesser resignations in Theresa May’s “The Headmistress Writes” spoof diary in the satirical magazine: “Assorted other members of staff whose names I can’t remember. (Subs, please put names in here). (Message from subs: sorry we can’t remember who they are either)….”

Though no one would put it quite like this, as a black man of Ghanaian origin who read PPE (Philosophy, Politics and Economics) at Oxford where he was president of the debating society, Gyimah had symbolic value in the Conservative Party.

His following increased after he appeared to quote from Harry Potter during Question Time on BBC TV.

When discussing President Trump’s retweets about the Right-wing party, “Britain First”, and May’s condemnation, he referenced Albus Dumbledore and quipped: “It takes great bravery to stand up to your enemies, it takes even more bravery to stand up to your friends.”

More pertinently, he appears to have made a valid point in his resignation statement — that Britain has been cut out from the Galileo satellite navigation system by the EU despite having invested £1.24 billion in the project which is meant to be a rival to the American GPS.

Galileo will be used by EU governments, citizens, military and industry. Although British scientists and engineers have helped to develop its crucial portions, the EU has said that the UK will not have access to the high-security encrypted parts of the system after Brexit.

Gyimah said this was a foretaste of the “brutal negotiations” to come when Britain seeks to negotiate a permanent trade agreement with the EU at the end of the transitional period.

“Our interests will be hammered because we will have no leverage,” he said on Saturday on BBC Radio 4’s Today programme.

The need for British scientists to continue to work closely with their counterparts in 27 EU countries have also been emphasised repeatedly by the president of the Royal Society, Prof Sir Venkatraman Ramakrishnan.

In Argentina, May confirmed the UK will instead aim to build its own global navigation satellite system, at a cost estimated by independent experts at £3-£5bn.

She said that “given the Commission’s decision to bar the UK from being fully involved in developing all aspects of Galileo, it is only right that we find alternatives.

“I cannot let our armed services depend on a system we cannot be sure of. That would not be in our national interest. And as a global player with world-class engineers and steadfast allies around the world, we are not short of options.”

Meanwhile, Amnesty International’s director in London, Kate Allen, has urged her to take up human rights abuses, bracketing India with Turkey and China.

“With Prime Minister (Narendra) Modi, we’d like Theresa May to ask for assurances that NGOs like Amnesty India and Greenpeace India will be able to continue their operations unhindered by politically-motivated restrictions,” she said.