Former US defence secretary Donald Rumsfeld insisted Tuesday that further United States arms sales to Taiwan were needed as China continued with its ambitious military modernisation plans.

Rumsfeld, who considers himself "a longtime friend of Taiwan", urged the island to keep seeking weapons from the US, and said it should not be upset by Washington refusing to sell it advanced fighters.

In a speech organised by a non-profit think tank in Taipei, Rumsfeld said: "As Taiwan identified further requirements and those needs are assessed as legitimate and reasonable in light of China's military posture, Taiwan has the responsibility to continue to make known its requests for responsible consideration.

"In turn, the United States has the responsibility to give such requests fair, prompt and reasonable attention. Taiwan deserves no less from a fellow democracy."

The remarks came after Washington announced last month it would equip Taiwan's 146 US-made F-16A/Bs with new technologies in a $5.85 billion deal.

The deal fell short of the island's fervent wish for 66 new and more powerful F-16 C/Ds even though Taipei and Washington both said that sale was still under consideration.

Although last month's arms package was less than what Taiwan had hoped for, it triggered an angry response from China, which warned that military ties with the United States would be hurt as a result.

Rumsfeld hailed the ongoing detente Taipei has been pursuing with China over the last three years.

He added: "Progress is likely to continue only if both parties recognise that armed conflict is an unacceptable option.

"That means it is in Taiwan's interest to maintain its defence and expand ties with its regional allies."

Rumsfeld was defence secretary in the Bush administration in 2001 when it approved the sale of eight conventional submarines to Taiwan as part of Washington's most comprehensive arms package to the island since 1992.