BEIRUT, Lebanon (AP) _ A Christian leader said today missing Anglican Church envoy Terry Waite is being held in west Beirut and ''Syria has him under control.''

Dany Chamoun, leader of the National Liberal Party, said in an interview in Christian east Beirut that his information was ''fairly accurate and reliable.''

There have been a number of unconfirmed reports on Waite, who dropped from sight Jan. 20 on a mission to free foreign hostages.

Chamoun would not disclose his sources but said: ''I have a lot of confidence from past experience and these people have proved they're always reliable on the information they've given me.''

Chamoun, a Maronite Catholic, is known to be on good terms with Druse warlord Walid Jumblatt, whose militiamen protected Waite before he disappeared in west Beirut.

No group has claimed to hold Waite.

''He (Waite) is with the Syrians, or I mean, not directly with the Syrians. Syria has him under control,'' said Chamoun, who spoke in fluent English.

He said he doubted recent reports that the Anglican Church envoy was being held at the Iranian Embassy in Moslem west Beirut. Iran has denied the reports.

Chamoun also said Western governments have bowed to pro-Iranian Moslems holding foreign hostages in Lebanon and ''have become hostages in their hostage policy.''

He maintained that Syria, which sent 7,500 troops into west Beirut on Jan. 22 to quell miltia warfare, was behind the chaos in west Beirut because it armed and supported Moslem radicals.

''They (the Syrians) brought in the people who have created the situation, and they have supported them with arms and weapons. .. . Syria is responsible for every single hostage taken which has been taken in Lebanon. ... They supported and they encouraged'' hostage-taking, Chamoun said.

Syria has had troops in northern and eastern Lebanon since 1976. The Syrian government has maintained it has worked to win the release of foreign hostages.