The arrival here of U.S. envoy Morris Draper for talks on a pullout by foreign forces from Lebanon has been delayed by at least two days because he has a stomach ailment, sources said today.

Draper had been expected to land in Beirut yesterday, and some news agencies quoting local radio reports mistakenly said he had arrived. He now is expected to arrive on Wednesday at the earliest.

Sources said they expected Draper to bring a proposal for a partial pullback of foreign troops as a first step toward a complete withdrawal of Israeli, Syrian and Palestinian forces.

A Beirut newspaper, quoting a Western diplomatic source, reported that one potential hitch involved Israel's desire to establish a framework for diplomatic talks, which would be aimed at reaching an accord to guarantee that Israel will be safe from attacks from southern Lebanon. The Lebanese government strongly opposes anything resembling formal negotiations with Israel, according to sources.

The newspaper, the French-language daily L'Orient-Le Jour, also quoted informed sources as saying that the expected U.S. plan proposes the following steps:

* Establishment of Lebanese state authority throughout Beirut and particularly in Christian East Beirut. The government has drawn criticism for delaying full deployment of the Lebanese Army in East Beirut, base of the Christian militia linked to the Phalangist Party of President Amin Gemayel.

* Deployment of the Lebanese Army within a month to an area outside Beirut bounded by a line stretching from Nahr el Kelb about seven miles north, to Mtein about 13 miles east, to the Damur River in the south. This apparently would involve a larger pullback by the Israelis than by the Syrians or Palestinians. An expanded multinational peace-keeping force--currently including U.S., French and Italian troops--would support the Lebanese Army in policing the area.

* A complete, simultaneous withdrawal by Israel, Syrians and Palestinians from all parts of the country, with details to be worked out later.