WRAPUP 3-Hong Kong pushes bill allowing extraditions to China despite biggest protest since handover

(Adds U.S. State Department spokeswoman)

* Lam says postponing bill will cause "divisiveness"

* Organisers say more than a million people demonstrated

* Broad opposition to proposal to allow extradition to China

* U.S. says Hong Kong's special status at risk

By James Pomfret and Farah Master

HONG KONG, June 10 (Reuters) - Hong Kong leader Carrie Lam vowed on Monday to push ahead with amendments to laws allowing suspects to be extradited to mainland China, a day after the city's biggest protest since its handover from British to Chinese rule in 1997.

Riot police ringed Hong Kong's legislature and fought back a group of several hundred protesters who stayed behind early on Monday after Sunday's peaceful march that organisers said drew more than a million people, or one in seven of the city's people.

"I don't think it is (an) appropriate decision for us now to pull out of this bill because of the very important objectives that this bill is intended to achieve," a sombre Lam told reporters while flanked by security and justice chiefs.

"While we will continue to do the communication and explanation, there is very little merit to be gained to delay the bill. It will just cause more anxiety and divisiveness in society."

The protests plunged Hong Kong into political crisis, just as months of pro-democracy "Occupy" demonstrations did in 2014, heaping pressure on Lam's administration and her official backers in Beijing. Chants echoed through city streets on Sunday calling on her to quit. "Extradite yourself, Carrie!" one placard read.

The rendition bill has generated unusually broad opposition, from normally pro-establishment business people and lawyers to students, pro-democracy figures and religious groups fearing the further erosion of Hong Kong's legal autonomy and the difficulty of ensuring even basic judicial protections in mainland China.

U.S. State Department spokeswoman Morgan Ortagus said on Monday that Washington was gravely concerned about the proposed amendments and warned that "continued erosion of the 'one country, two systems' framework puts at risk Hong Kong's long-established special status in international affairs."

She said the United States was concerned the amendments could damage Hong Kong’s business environment "and subject our citizens residing in or visiting Hong Kong to China’s capricious judicial system."

Any amendments "should be pursued with great care and in full consultation with a broad range of local and international stakeholders who may be affected," she said.