Menendez would be the first Latino to head the Foreign Relations Committee. He will preside at two high-profile hearings this week, Wednesday with Clinton and again on Thursday at Kerry's confirmation hearing.
Royce, 61, is a Californian who got his political start in the youth movement for Ronald Reagan. Democrats and Republicans recall his efforts to ensure the extradition of Viktor Bout, a Russian arms dealer convicted in the United States on terrorism charges last year and sentenced to 25 years in prison.
Royce has assumed the chairmanship of the House Foreign Affairs Committee, replacing Rep. Ileana Ros-Lehtinen, the Florida Republican who had to step down due to Republican term limits on committee chairmen.
"He's very thoughtful, very intelligent. He's serious, he cares about the issues. I've only good things to say," Democratic Rep. Nita Lowey of New York, the ranking member on the House Appropriations Committee, said of Royce.
Menendez, now starting his second full Senate term, has been willing to challenge Republican and Democratic administrations.
He voted against the Iraq war in 2002, tangled with fellow Democrats on Cuba and pushed the Obama administration on sanctions on Iran. In just over a year, Congress has approved three rounds of penalties on Tehran's banking, energy and shipping industries to thwart its nuclear ambitions, with Menendez joining forces with Republican Sen. Mark Kirk of Illinois.
He suggested it might be time to pause and make sure the penalties are working — a possibility the administration probably would welcome.
"I don't know that there will be any new sanctions," Menendez said in a recent interview. "I think that the enforcement of existing sanctions and the new set of sanctions that don't go into effect yet and how we enforce those and how we pursue them ... will be very important in our success, hopeful success, to have Iran not achieve nuclear power."
Royce gives Menendez high marks for his work on sanctions — "cutting edge of really debilitating sanctions," the Republican says — and is eager to join forces on another round.
"I'd like to target the entire Iranian energy sector," Royce said. "I'd like to make it even harder for foreign companies to sell commercial goods to Iran. I'd like to freeze the regime's remaining foreign currency reserves."
Royce is optimistic about working with Menendez despite the political divide and the decades since the two committees produced major authorization legislation.
Royce said that during his travels with Menendez, the senator shared his strong opinion of totalitarian regimes.
"He has firsthand experience in his own family with that in terms of what happened to his uncle, a labor leader in Cuba who was executed there," the congressman said.
Menendez is reluctant to discuss his family, but he elaborates on his worldview and his approach to foreign policy.
"Dictatorship and totalitarianism regardless of where it exists in the world is utterly anti-democratic, it oppresses the people," he said, adding that promotion of democracy is critical.
The New Jersey senator has won praise from the families of those killed when U.S.-bound Pan Am Flight 103 was blown out of the sky over Lockerbie, Scotland, in 1988 and for his diligence in challenging Moammar Gadhafi and any U.S. efforts to reach out to the late Libyan leader.
"He didn't let us down," said Brian Flynn, whose brother John was killed. "There's a certain amount of integrity and loyalty, and you saw that."
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