Taiwanese shouting anti-communist slogans staged protests at an airport and a school on Monday against a visit by a top Shanghai official which they see as intended to promote China's unification with Taiwan.

Sha Hailin, a standing committee member of the Communist Party in the city and head of the United Front Work Department there, is the highest-level mainlander to visit since cross-strait ties worsened under Taiwan's new government.

He arrived in Taipei for an annual forum on municipal exchanges as protesters shouted "Sha Hailin, go back to China!" at the capital's Songshan airport.

Dozens of demonstrators waved placards reading "Expel propaganda communist, defend Taiwan's sovereignty" and "(Taipei mayor) Ko Wen-je sells out Taiwan". Some supporters also rallied outside the airport with welcome signs.

While most demonstrators were cordoned off, one man holding a poster got into the airport arrivals hall and shouted "Sha Hailin, get out!" as Sha walked by.

The protester scuffled briefly with policemen before being taken away.

Scores of protesters rallied again when Sha visited a high school to open a sports festival and played table tennis with Taiwanese students.

Relations with China have grown increasing frosty since Tsai Ing-wen of the Democratic Progressive Party won the presidency in January. Beijing is highly suspicious of Tsai because her party is traditionally pro-independence, and has warned her against any attempt at a breakaway.

China's Taiwan Affairs Office announced it had suspended official contact with Taipei after Tsai's government, which took office in May, failed publicly to accept the "one China" principle which governed relations under her predecessor.

Sha stressed that the basis for peaceful cross-strait relations was the recognition of "one China".

"If we want to maintain peaceful developments in cross-strait ties, I believe the political basis cannot be avoided... We will continue to work hard to build and solidify this political basis," Sha, who heads the visiting delegation in place of Shanghai Mayor Yang Xiong, told reporters.

Asked about the protests, he said: "There were also many people who welcomed me. Their voices were small but their number was bigger."

Taiwan has been self-ruling since splitting with the mainland in 1949 following a civil war but has never formally declared independence. Beijing still sees it as part of its territory awaiting reunification, by force if necessary.

Critics claim Sha, as Shanghai's propoganda chief, intends to push during his visit for reunification and accuse Taipei mayor Ko of "selling out" to Beijing.

"We are very angry and we refuse China's propoganda to reunify Taiwan. Taiwan is an independent country. We must maintain our sovereignty and dignity," said protester Sherry Huang from the pro-independence Taiwan Solidarity Union (TSU) party.

"China has long wanted to annex Taiwan and we don't need to continue exchanges with it," said protester Hsu Ya-chi.

The TSU said it planned another demonstration Monday night at a welcome dinner for the Shanghai delegation in Taipei city hall, and vowed to protest throughout Sha's stay.