Chinese officials have announced unspecified sanctions on US house speaker Nancy Pelosi over her visit to Taiwan earlier this week.

A Chinese foreign ministry statement said that Ms Pelosi had disregarded China’s concerns and resolute opposition to her visit to the self-ruled island.

Ms Pelosi was the highest-ranking US official to visit the self-governing island in 25 years. China claims Taiwan as its own territory and opposes it having its own engagements with foreign governments.

Earlier, US secretary of state Antony Blinken said that Chinese military exercises aimed at Taiwan – including missiles fired into Japan’s exclusive economic zone – represent a “significant escalation”.

The military drills were launched by China after Ms Pelosi’s visit sparked fury in Beijing.

At a news conference in the Cambodian capital Phnom Penh, Mr Blinken said: “China has chosen to over-react and use Speaker Pelosi’s visit as a pretext to increase provocative military activity in and around the Taiwan Strait.”

Taiwanese fighter jetsTaiwan Air Force Mirage fighter jets taxi on a runway at an airbase in Hsinchu (AP)

Mr Blinken also said the US stands in “strong solidarity” with Japan following the “dangerous actions China has taken”.

Speaking on the sidelines of a meeting with the Association of Southeast Asian Nations (Asean) in Cambodia, Mr Blinken said that Ms Pelosi’s visit was peaceful and did not represent a change in American policy towards Taiwan.

He said the situation had led to a “vigorous communication” during East Asia Summit meetings in Phnom Penh in which both he and Chinese foreign minister Wang Yi took part along with the Asean nations, Russia and others.

“I reiterated the points that we made publicly as well as directly to Chinese counterparts in recent days, again, about the fact that they should not use the visit as a pretext for war, escalation, for provocative actions, that there is no possible justification for what they’ve done and urge them to cease these actions,” he said.

Mr Blinken did not sit down one-on-one with Mr Wang but said he had spoken with the Chinese foreign minister already about the possibility of a visit by Ms Pelosi to Taiwan before it had taken place during meetings in Bali, and had made the US position clear.

As the East Asia Summit opened, Mr Wang patted Russian foreign minister Sergei Lavrov on the shoulder as he entered the room and gave the already-seated Mr Lavrov a quick wave before taking his own seat.

Mr Lavrov waved back in response.

Chinese jetsChinese jets (Xinhua via AP)

Mr Blinken, who entered the room last, did not even glance at Mr Lavrov as he took his own seat about a half-dozen chairs away, or at Mr Wang who was seated farther down the same table as Lavrov.

Ahead of the Phnom Penh talks, the US state department indicated Mr Blinken had no plans to meet one-on-one with either man during the course of the meetings.

On Thursday, China cancelled a foreign ministers’ meeting with Japan to protest a statement from the Group of 7 nations that said there was no justification for Beijing’s military exercises, which virtually encircle Taiwan.

“Japan, together with other member of the G7 and the EU, made an irresponsible statement accusing China and confounding right and wrong,” Chinese foreign ministry spokeswoman Hua Chunying said in Beijing.

When Japan’s foreign minister Hayashi Yoshimasa began to speak Friday at the East Asia Summit, both Mr Lavrov and Mr Wang walked out of the room, according to a diplomat in the room.