PRAGUE — The Czech government firmly favors hosting an American missile defense site but believes it will take longer to negotiate a deal than American officials had hoped, a senior Czech official said today.

A deputy minister of foreign affairs, Tomas Pojar, told American reporters traveling with Defense Secretary Gates that his government’s support is based not only on a shared worry about future missile threats but also a “moral, historical” sense of appreciation for American support for Czech democracy.

He also stressed that Prague does not intend to rush a deal, and he predicted that it will be difficult to win approval in parliament.

“I think it’s going to take a few more months” than the American timetable, which calls for completing negotiations by the end of the year and winning parliamentary approval next spring, Mr. Pojar said in an interview over breakfast at the Ministry of Foreign Affairs while Mr. Gates was meeting with President Klaus.

Mr. Pojar said he takes little stock in public opinion polls that show a majority of Czechs oppose having an American missile defense site on their territory.

Mr. Gates later held talks with Defense Minister Vlasta Parkanova and was scheduled to meet with Prime Minister Mirek Topolanek as well as with members of parliament with a range of views on missile defense.

The Pentagon wants to install 10 interceptor rockets in Poland which, when linked to a proposed tracking radar in the Czech Republic and to other elements of the existing American missile defense system based in America, could defend all of Europe against a long-range missile fired from the Middle East.

Poland’s opposition party ousted ruling conservatives in parliamentary elections on Sunday, which is expected to mean some delay in missile defense negotiations with Washington. Nonetheless, Mr. Gates said yesterday he still believes Warsaw will cooperate.

Mr. Gates, asked about possible ramifications of the Polish elections for the Pentagon’s missile defense expansion plan, said America has enjoyed good cooperation from Poland regardless of the makeup of its government.

The Polish opposition favors hosting an American missile base, but it has criticized the outgoing government for not taking a tougher stance in negotiations.

“I expect that cooperation to continue,” Mr. Gates said in Kiev, Ukraine, while making no firm prediction. “Obviously we’ll have discussions with the new government of Poland in terms of their specific plans. We clearly are hopeful that the kind of cooperation we’ve enjoyed recently — both in Iraq and Afghanistan on the one hand, and in moving toward negotiating an agreement on missile defense — will continue as before.”

Critics say no such system is needed in the foreseeable future because no country in the Middle East, including Iran, now possesses a ballistic missile with sufficient range to threaten all of Europe or America.