"The defense minister is currently meeting with the two-member congressional delegation at Defense Ministry headquarters to discuss the situation in Egypt and follow up on progress made on the [transitional] roadmap," the source, preferring anonymity since he is not authorized to speak to the media, told Anadolu Agency.
The delegation, led by Republican congressman Mike Rogers (head of the Permanent Select Committee on Intelligence in the US House of Representatives), arrived on Monday night for two days of talks with senior Egyptian officials.
Members of the US delegation are also expected to meet with interim President Adly Mansour.
The visit comes only a few days after al-Sisi concluded a visit to Moscow, where he agreed with Russian officials on the need to step up military relations between Russia and Egypt – the latter a longstanding US ally.
In November, Russian Defense Minister Sergei Shoigu and Foreign Minister Sergei Lavrov both visited Cairo – the first such visit by a Russian defense minister since 1971.
Al-Sisi, widely seen as the driving force behind last July's ouster of elected president Mohamed Morsi by the army, is widely expected to run in Egypt's upcoming presidential elections.
The military chief, however, has not stated decisively whether or not he plans to vie for top office. Speculation has been rife, however, that he would soon resign his military post in advance of announcing a presidential bid.
No date has yet been set for Egyptian presidential polls, but they are expected sometime within the next three months.
Presidential elections represent the second step in an army-imposed roadmap for political transition, unveiled by al-Sisi in the wake of Morsi's overthrow.