The ruling in the International arbitration case between China and the Philippines must be binding, according to Hugo Swire, British Minister of state assigned to East Asia, Reuters UK reported.
On Wednesday, China expressed anger at the senior British official's comments while reiterating the country's claim over virtually all of the South China Sea.
"The comments by Mr. Swire neglect the facts and are very discriminatory and one-sided and seriously go against Britain's promise to take sides," said Hua Chunying, spokeswoman for the Chinese Foreign Ministry, during a news briefing.
For Swire, Britain sees the expected Hague court ruling as an opportunity for China and the Philippines to mend ties and settle their territorial disputes.
In recent months, tensions have been high as China continues to engage in the building of artificial islands in contested waters. The country also maintains that the Permanent Court of Arbitration has no jurisdiction in the case.
According to Hua, tensions in the South China Sea are the result of the machinations of the United States and the Philippines, as the two countries continue to facilitate military drills and ship patrols.
"The facts prove that if the South China Sea dispute remains tense, then it's the U.S. which is the main cause of this," said Hua.
The court is expected to rule in late May or early June. Last February, the United States and the European Union warned China it should respect the Hague's ruling. Experts point out that the Court has no way of enforcing its rulings and that China will continue to shun the Court's authority as a result.
Britain and China have strengthened economic ties last October during President Xi's state visit. Critics have criticized Britain for prioritizing financial gain over human rights and security interests.
The U.S. administration also expressed its disapproval when Britain became the first country outside of Asia to be included in the Group of Seven advanced economies supporting a China-backed development bank in Asia. The bank is largely seen by critics as an unwelcome rival to the western-led World Bank.
Aside from the Philippines, countries such as Brunei, Malaysia, Taiwan and Vietnam also have territorial claims in the South China Sea.