Ghaith R. Pharaon, the wealthy Saudi Arabian investor who owns 16 percent of Hyatt International Corp.'s stock, today said he would pay $30 a share to all shareholders to acquire the hotel chain.

Last month the company, which is controlled by the wealthy Pritzker family of Chicago, said it planned to go private and buy out all minority shareholders, including Pharaon, for $22 a share. Goldman, Sachs -- the big New York investment house -- determined that $22 was a "fair" and equitable" price for the Hyatt International shares, the company said.

Because the Pritzker family owns 74 percent of the Hyatt International's stock, approval of the company's move to be privately held is assured.

A spokesman for the Pritzkers said late today that they will not accept the Pharaon proposal and intend to go ahead with their plan to take the company private for $22 a share. The formal vote on the Pritzker proposal will occur at the company's annual meeting, scheduled for May.

Observers said that Pharaon's announcement today appears to be an attempt by him to boost the price he will receive from the Pritzker family for 16 percent of Hyatt International stock owned by his Interedec (USA) Inc.

Last month negotiations broke down between Pharaon and the Pritzkers, who sought to buy the Saudi businessman's Hyatt International holdings.

Hyatt International runs the 36 Hyatt hotels located outside the United States.In 1979 Hyatt Corp., which runs the Hyatt hotels within the United States, went private.

Pharaon's Interedec tried to acquire Hyatt International in late 1978, but the Pritzkers beat back the challenge although Pharaon ended up with the largest minority shareholding in Hyatt International. The remaining 20 percent of Hyatt International stock is traded in the over-the-counter market.

In making his offer, Pharaon said he did not think the Pritzker's proposal to buy out the minority shareholder at $22 a share and take the company private "reflects the value of Hyatt International's shares." He said that the proposal he has made is "fair and generous" and would result in a company stronger and more profitable than the Hyatt International that would result from the Pritzker proposal.