The Philippines said today it had lodged a formal protest at the United Nations over China's claims to the Spratly islands and adjacent South China Sea waters. A Foreign ministry spokesman said the newest controversy in the decades-old multi-lateral dispute centres on formal notes sent by China to the UN Secretary General in 2009 outlining the basis of its claim. The Philippines and China, along with Brunei, Malaysia, Taiwan and Vietnam, claim all or part of the Spratlys, which are believed to sit on vast mineral resources. Manila last month complained that Chinese patrol boats inappropriately harassed a Philippine oil exploration vessel in disputed waters near the Spratlys. The Philippines later announced plans to pursue oil exploration in the South China Sea and to upgrade a military airfield on Thitu island.Thitu is the largest of the seven Spratly islands that the Philippines occupies. The Philippines claims more than 50 islands in the archipelago. China has recently reiterated its exclusive claims to all the disputed areas and their adjacent waters, much of which is closer to Philippine land than Chinese.