British Prime Minister David Cameron arrived in Cairo on Monday, a British embassy official said.
Cameron's visit makes him the first foreign leader to visit the Egypt since the downfall of former president Hosni Mubarak.
Cameron will speak to anti-Mubarak opposition figures, but not the Muslim Brotherhood.
"I think this is a great opportunity to talk to those currently running Egypt to make sure this really is a genuine transition from military rule to civilian rule," the prime minister said before arriving in Cairo.
A British official travelling with Cameron said he would meet members of the former opposition to Mubarak but not the Brotherhood, which is regarded with suspicion in the West.
Earlier today, American Under Secretary of State for Political Affairs William Burns started a three-day visit to Egypt. During his trip he will meet with Amr Moussa, secretary general of the Arab League, who has already announced he will run in presidential elections later in the year.