WASHINGTON, Aug 18 (Reuter) - The United States said on Friday that most Americans planning to attend a U.N. women's conference in China have not received visas and pressed Beijing to honour its commitment to facilitate the paperwork.

"The Chinese government has not issued them (visas) as promptly as we think they should be issued and we are continuing to press them to do so," State Department deputy spokesman David Johnson told reporters.

He declined to ascribe any political motives to the slow process, as other critics have done. But the conference, which is to be held in Beijing, and a parallel private forum to be held outside the capital could become another irritant in already raw relations between China and the United States.

Undersecretary of State Peter Tarnoff, who will visit Beijing next week for wide-ranging talks, is expected to raise the visa issue during his meetings.

"The overwhelming majority of U.S. citizens planning to attend the meetings in China do not yet have visas," Johnson acknowledged at a news briefing.

"Very few applications have actually been denied, though many who have applied with all necessary documentation have been instructed t considers hostile, have been refused visas outright. Many others have encountered bureaucratic obstacles in the vias process that some groups fear are aimed at limiting attendance at the forum generally.

Johnson said the adminstration had made it clear to Beijing that the United States considers the NGO forum a "fundamental and integral part (of the conference) and that we expect them to facilitate the participation of non-governmental organisations at this conference."

Asked if the United States thought China was excluding certain groups, he said so few visas have been granted it would be impossible to draw any conclusion.

He said the United States has also made its concerns known to senior U.N. officials but he pointedly placed the onus for delays on China.