(Adds U.S. State Department comment)
BEIJING, July 19 (Reuters) - China's government warned on Tuesday that it would take "forceful measures" if U.S. House of Representatives Speaker Nancy Pelosi visited Taiwan, after the Financial Times said https://on.ft.com/3B0jKgc she would go to the Chinese-claimed island next month.
Pelosi and her delegation will also visit Indonesia, Japan, Malaysia and Singapore, and spend time in Hawaii at the headquarters of U.S. Indo-Pacific command, the London newspaper added, citing people familiar with the matter.
Taiwan's Foreign Ministry said it has "not received relevant information" about any visit.
Asked about the report, Drew Hammill, Pelosi's deputy chief of staff, said, "We do not confirm or deny international travel in advance due to longstanding security protocols."
The Democratic leader's visit to Taiwan had been postponed from April, after she tested positive for COVID-19. At the time, China said such a visit would severely affect Chinese-U.S. relations.
Speaking in Beijing, Chinese Foreign Ministry spokesman Zhao Lijian said any visit by Pelosi would "seriously undermine China's sovereignty and territorial integrity".
"If the U.S. side obstinately clings to this course, China will definitely take resolute and forceful measures to firmly defend its national sovereignty and territorial integrity," he said. "The United States must be fully responsible for all the consequences caused by this."
U.S. State Department spokesperson Ned Price, asked about China's reaction, said: "I believe the foreign ministry was weighing in on a hypothetical. That is something that I will hesitate doing here".
Taiwan faces mounting pressure from China, which considers the democratically governed island its own territory. The issue is a constant irritant in ties between Beijing and Washington.
Taiwan, however, has been heartened by continued support offered by U.S. President Joe Biden's administration, which has repeatedly spoken of its "rock-solid" commitment to the island.
Pelosi, a long-time critic of China, held an online meeting with Taiwanese Vice President William Lai in January as he wrapped up a visit to the United States and Honduras.
The White House had expressed concern about the Pelosi trip, the Financial Times said, citing three people familiar with the situation.
There were divisions in the Democratic U.S. administration over whether Pelosi should visit Taiwan, the FT quoted two sources as saying.