“Discussions to this end are ongoing, hence the proposed trip will not take place this week. The EU remains open to a future visit, taking into account our expectations,” the spokesman added.

A diplomatic source from an EU member state told the South China Morning Post that the states would not take individual actions on this matter, and would instead wait for “EU coordination” for a “collective decision”.

A visit by all EU member countries would be the first by a large group of Western diplomats to the area since Beijing’s security clampdown in Xinjiang seized international attention over the last year.

China has been repeatedly condemned by foreign governments and human rights groups on human rights abuses reportedly committed in Xinjiang, where detention camps were reported to be holding more than one million ethnic Uygurs and other Muslims for political re-education.

Former detainees have told foreign news organisations that they were subjected to abuse and torture at the centres, and some have testified about their experiences before the US Congress – charges which Beijing consistently denies.

According to Beijing, the centres are “pre-emptive measures against extremism” that offer “trainees” job and other life skills.

Late last year, a group of 15 Western diplomats from France, Britain, Germany and the EU’s top envoy in Beijing asked to meet with Xinjiang’s top official, Communist Party chief Chen Quanguo, to discuss their concerns about the situation in Xinjiang.

However China has only allowed limited access for carefully selected groups of journalists and diplomats to the area, most of them from non-Western countries.

A three-day visit by a delegation that included EU countries took place at the end of February, when diplomats from Hungary and Greece, as well as Myanmar, Algeria, Morocco, Vietnam, Singapore and the mission of the League of Arab States in China visited Xinjiang.

The invitation to the larger EU contingent was sent on Thursday, the day Chinese President Xi Jinping began a six-day European state visit to Italy, Monaco and France.

In addition to meeting French President Emmanuel Macron – among EU leaders, an outspoken critic of China – Xi is to meet German Chancellor Angela Merkel and European Commission President Jean-Claude Juncker in Paris on Tuesday, before he ends his trip.

The tour, Xi’s first overseas state visit this year, is China’s latest effort to ease fears that it is a “systemic rival” to the EU, as identified in a European Commission report this month. Good relations with the EU have grown more important for China as it remains mired in a trade war with the United States.

EU countries are split over China’s growing influence on the continent and tactics that some claim are intended to divide the bloc. While some are welcoming towards Chinese investments, others remain sceptical.

During Xi’s visit on Saturday, Italy confirmed becoming the first Western European power to join China’s multibillion “Belt and Road Initiative”. Still, the US is applying great pressure on the European Union to shut out Chinese telecommunications equipment maker Huawei Technologies from participating in the next-generation 5G networks, citing cybersecurity risks.

A series of EU meetings involving China are scheduled in the coming weeks: a EU-China summit in Brussels, Belgium, is set for April 9, while the 16+1 summit of China and countries from central and eastern Europe is scheduled in Dubrovnik, Croatia, on April 12.