The first Republican presidential debate is less than a week away, and many are speculating about the role businessman Donald Trump will play as he leads the GOP field. Which Republicans will be on the stage to take on Trump? Plus, Congress is heading out of town for its five-week summer recess while leaving some major issues unresolved.

The new nuclear deal with Iran has managed to rile up some in the U.S. and abroad. With the disapproval of Israeli Prime Minister Benjamin Netanyahu and politicians alike, the new deal leaves questions in its wake. Reporters break down the deal's future implications. Plus, a report on the staggering political fundraising that will impact the race to 2016.

In the wake of the announcement of a nuclear agreement with Iran, President Obama used an extended session with the White House Press Corps to make his case. Meanwhile, Vice President Joe Biden went to the Capitol to begin discussing the deal with lawmakers. Gwen Ifill reports on the efforts to persuade Congress and the American public.

On the day that Iran, the U.S. and five other world powers announced a historic agreement on its nuclear program, National Security Advisor Susan Rice joins Gwen Ifill to discuss the rules that ensure governing sanctions relief and whether President Obama is serious about using his veto power should Congress reject the deal.

As the June 30 deadline nears for the nuclear talks with Iran, we look back in the Washington Week Vault to June 2006 when the United States joined with the five permanent members of the UN Security Council as well as Germany to propose discussions with Iran to suspend its nuclear enrichment program. Bloomberg's Janine Zachariah joins Gwen Ifill to explain the proposal.

Voting 98 to 1, the Senate passed the Iran Nuclear Agreement Review Act, a bill that would give Congress up to 52 days to review any proposed nuclear agreement with Iran, during which President Obama would be barred from reducing imposed sanctions. Gwen Ifill gets two views on the overwhelming support for the measure from Sen. John Thune, R-S.D., and Sen. Tim Kaine, D-Va.

Kentucky Sen. Rand Paul became the second official 2016 candidate this week, but how is he distinguishing himself as a different kind of Republican as he tries to win the GOP presidential nomination? With two other candidates set to join the race in the coming days -- Democrat Hillary Clinton on Sunday and Republican Marco Rubio on Monday, how is the 2016 field taking shape?

This week, a deal was finally reached between Iran and other world powers over Iran’s nuclear power. Indira Lakshmanan of Bloomberg News details what she found out in Lausanne, Switzerland. Why announce an official presidential campaign in April?

After weeks of marathon talks in Switzerland, world leaders reached a preliminary agreement on the future shape of Iran's nuclear program. Indira Lakshmanan of Bloomberg News just returned from the talks and debriefs on the terms of the deal that include limitations on Iran's nuclear capabilities and a lifting of economic sanctions.

No deal was reached over Iran’s nuclear program on Wednesday, but talks seemed to be headed into yet another day, with Iran and the U.S. each indicating it’s up to the other to bridge the gap. Gwen Ifill gets an update on the negotiations from Indira Lakshmanan of Bloomberg News.