BEIJING (REUTERS) - The foreign ministers of Ireland, Poland, Hungary and Serbia will visit China from Saturday (May 29), the Chinese foreign ministry said, in a sign of a push to strengthen ties with Europe after an investment treaty was frozen.

The European Parliament this month halted ratification of the pact until Beijing lifts sanctions on European Union (EU) politicians, deepening a dispute in relations and denying EU companies greater access to China.

Beijing's sanctions were a response to Western ones against Chinese officials accused of the mass detentions of Muslim Uighurs in north-western China.

The four ministers will visit China from May 29 to 31 at the invitation of Foreign Minister Wang Yi, ministry spokesman Zhao Lijian told a regular news conference in Beijing on Friday.

During the visit, Mr Wang will separately meet the ministers and discuss bilateral and China-Europe relations, said Mr Zhao. Beijing hopes the visit can help deepen cooperation and "promote the post-epidemic economic recovery", he added.

EU members Poland and Hungary, as well as Serbia, which is not in the bloc, belong to the China-led "17+1" grouping of Central and Eastern European countries. The grouping recently lost a member when Lithuania pulled out.

Lithuania's parliament in May described China's treatment of its Uighur minority as genocide, and the country also said it would open a trade representative office this year in Taiwan, which Beijing considers its own territory.

The ministers invited to China are not from countries whose parliaments have branded its treatment of the Uighurs as genocide, a label Beijing strongly rejects.

Serbia and Hungary have also both approved and administered Chinese vaccines against Covid-19.