* Lam says relief measures to be introduced in near-term
* Anti-government protests planned throughout the week
* Retail sales, economy battered as protests take toll (Adds report about Lam's trip to Beijing)
By Noah Sin and Clare Jim
HONG KONG, Dec 3 (Reuters) - Hong Kong leader Carrie Lam on Tuesday said U.S. legislation supporting protesters may damage business confidence in the financial hub, and announced a fourth round of relief measures to boost an economy battered by months of demonstrations.
Lam told reporters the Hong Kong Human Rights and Democracy Act signed into law by U.S. President Donald Trump last week, was "wholly unnecessary". Hong Kong, which has been convulsed by nearly six months of pro-democracy protests, is now grappling with its first recession in a decade.
The act requires the U.S. State Department to certify at least annually that Hong Kong retains enough autonomy to justify favourable U.S. trading terms, and threatens sanctions for human rights violations.
"The impact currently is on confidence," Lam said. Companies "will be worried about the actions the U.S. government may take in the future after they review this legislation," she said.
The sometimes violent unrest that has rocked Hong Kong represents the biggest challenge to stability for China's ruling Communist Party since the 1989 Tiananmen Square crackdown in Beijing.
Lam will visit Beijing on Dec. 16 and meet with Chinese President Xi Jinping, Hong Kong broadcaster Cable TV said on Tuesday, citing sources.
Separately, the justice secretary, Teresa Cheng, said she would return to her office on Wednesday after being on sick leave for more than two weeks following an altercation in London during which she was injured.
The Hong Kong government has previously said Cheng was targeted by a "violent mob" while on a trip to promote the city.
Cheng, who returned to Hong Kong from Beijing on Tuesday, told reporters at the airport that she had suffered a bone fracture around her wrist and had an operation in London.
"The hand is of course painful, but not as painful as the heart to see Hong Kong is still at the state we are in," she said.
BIG CHALLENGE
Lam did not specify what the next round of relief measures would include. The government has already offered around HK$21 billion ($2.7 billion) in economic support, particularly to help the transport, tourism and retail industries.
Retailers have been especially hard-hit. Hong Kong is famously a top shopping destination for Chinese tourists. But the unrest has scared off tourists and hit spending. Retail sales suffered their steepest fall on record in October.