Mr. Bush suspended talks after taking office last year.
Mr. de Klerk made some concessions, and the congress did not act on its ultimatum to suspend talks.
Their unions suspended formal talks last week.
If progress was not evident, it said, there would be no hesitation in directing the Congress's executive committee to suspend talks.
The attack led Israel to suspend talks with the Palestinians on the implementation of the peace agreement.
Japan has also suspended talks on loan packages estimated to total more than $5 billion.
However, violence resumed when Mehsud suspended talks in June.
Israel suspended talks with Syria a year ago after four suicide bombings by Islamic militants.
Beijing reacted to the bombing by suspending talks with the United States on military issues, arms proliferation and human rights.
The European Ministers reached agreement about suspending talks on a number of negotiation chapters.
