U.S. Secretary of State John Kerry will leave China “in absolutely no doubt” about Washington’s commitment to ensuring freedom of navigation and flight in the South China Sea when he visits Beijing this weekend, a senior State Department official said on Wednesday.

Setting the scene for what could be contentious encounters with Chinese leaders, including President Xi Jinping, the official said Kerry would warn that China’s land-reclamation work in contested waters could have negative consequences for regional stability – and for relations with the United States.

On Tuesday, a U.S. official said the Pentagon was considering sending military aircraft and ships to assert freedom of navigation around rapidly growing Chinese-made artificial islands in the disputed South China Sea.

China’s Foreign Ministry responded by saying that Beijing was “extremely concerned” and demanded clarification.

Read more: http://uk.reuters.com/article/2015/05/13/uk-usa-china-southchinasea-idUKKBN0NY1TY20150513