SHANGHAI/SEOUL (Reuters) - Pressure in China on travel firms forced airlines and cruise operators to cut routes to South Korea, as the fallout spread on Friday from a diplomatic row over Seoul’s plans to deploy a U.S. missile defense system against Beijing’s objections.

A Royal Caribbean cruise is seen at a port in Dalian, Liaoning province, China, July 20, 2017. Picture taken July 20, 2017. REUTERS/Stringer

China Eastern Airlines Corp Ltd 600115.SS and Spring Airlines Co Ltd 601021.SS stopped offering flights on their websites between the eastern Chinese city of Ningbo and popular South Korean tourist island Jeju from next week.

Korea’s Eastar Jet said it was halting flights between the South Korean cities of Cheongju and tourist hotspot Jeju with various Chinese cities including Ningbo, Jinjiang and Harbin.

This followed Carnival Corp's CCL.N Costa Cruises and Royal Caribbean Cruises RCL.N cutting South Korean visits by their China ships. Royal Caribbean cited "recent developments regarding the situation in South Korea".

The moves reflect a more aggressive and blatant stance against South Korean business in China, although Beijing has not directly said it is targeting South Korean firms.

An internal South Korean government document seen by Reuters said Chinese authorities gave a “7-point” verbal instruction to travel firms to curtail or ban trips to South Korea.

These included a ban on tour groups visiting South Korea from March 15, cruise ships not being allowed to dock in South Korea ports and a warning that those who violated the guidance would face “severe punishment”.

Reuters could not immediately reach China’s tourism administration for comment. China Eastern and Spring Airlines did not respond to requests for comment.

The crackdown has sent a chill across South Korea’s retail and tourism sectors, which rely heavily on China trade, and prompted South Korea to say it will consider filing a complaint against China to the World Trade Organization.

South Korea sold $124 billion worth of goods and services to China last year, about five times the amount it exported to nearby Japan and double the amount it shipped to its second-biggest overseas market, the United States.

Tourism is a particularly sensitive sector, with official South Korean data showing almost half of the visitors to the country come from China.

Asked about cruise operators cancelling South Korean port visits, an official from South Korea’s Ministry of Trade, Industry and Energy told Reuters the ministry was checking if any WTO rules have been violated.

“If we are to launch a dispute, we still need to make sure if anything has been ordered by Beijing,” the official said.

“RELEVANT DEPARTMENTS”

Political risk analysts said the widespread actions against South Korean firms pointed to centralized coordination.

Princess Cruises, also owned by Carnival, said in a statement on Friday it would remove visits to South Korea from routes after talks with “relevant departments”.

“Due to the current situation, Princess Cruises’ China team has been in close dialogue and prudent discussions with relevant departments,” the firm said. “All routes which involve South Korea have been altered.”

The diplomatic problems with its biggest trade partner have come at a difficult time for South Korea.

On Friday, South Korea’s Constitutional Court removed President Park Geun-hye from office on Friday over a graft scandal involving the country’s conglomerates.

Analysts said the upheaval had given China the opportunity to put pressure on Park’s possible successors to ditch or delay the installation of the U.S. Terminal High Altitude Area Defence (THAAD) missile system.

“I think they’ll keep up this pressure well into the period where we get a new government in South Korea,” said Andrew Gilholm, director of analysis for China and North Asia at risk consultancy Control Risks.

“Possibly the reason they’re pushing so hard is that they are trying to influence whatever policy the next government in Seoul takes.”

Meantime, South Koreans living in China have been advised by business groups to adopt a low profile, while residents and shopkeepers in a Shanghai neighborhood where many South Koreans live told Reuters of a growing sense of anxiety.

“I feel wherever I am people are watching me. On the street, in the car and at restaurants, I don’t feel I can freely speak Korean,” said Seo Lan Kyung, 48, a housewife who said she has been living in China for 18 years.

“I want to keep living here but increasingly there’s a feeling of impending crisis.”