When White House Press Secretary Robert Gibbs goofed and referred to "Secretary Kerry" on Wednesday, it seemed like one heck of a Freudian slip. 

But Sen. John Kerry, the Massachusetts Democrat and former presidential candidate -- fresh back from a successful diplomatic mission to Afghanistan -- is brushing off any suggestion that he's positioning for a promotion or stepping on the real secretary of state's toes. 

"I did not take steps in any freelancing way. I was in touch with Secretary Clinton constantly," Kerry told reporters Wednesday. "She encouraged me to stay at it, and I think we worked as an effective team." 

Kerry had a private meeting with President Obama Wednesday, after having helped persuade Afghan President Hamid Karzai to agree to a runoff election in his country. The White House has expressed its deep appreciation for his role in seeking some political resolution to the contested election. 

But Kerry has made sure to highlight that he had the full support of Secretary of State Hillary Clinton and Amb. Richard Holbrooke. 

Kerry said it was just a matter of circumstance, and that his years on the Senate Foreign Relations Committee enabled him to help the Obama White House. "It was frankly lucky that I planned a fact-finding mission," Kerry said. 

Gibbs said Kerry was instrumental in the negotiations because he happened to be in the region at the time. 

It's hardly the first time an official outside the administration has played a key diplomatic role on the world stage. Over the summer, former President Bill Clinton traveled to North Korea to negotiate the release of two imprisoned Americans; Sen. Jim Webb, D-Va., flew to Myanmar, also known as Burma, to bargain for the release of another American; and envoys from North Korea traveled to the United States for talks with New Mexico Gov. Bill Richardson. 

In Afghanistan, the August election is unresolved due to a number of issues -- primarily because neither of the two frontrunners won more than 50 percent of the vote to avoid a runoff. Claims of fraudulent ballots caused Karzai's percentage to drop below the 50 percent he claimed to have won. 

At the same time, Obama is currently deciding on a course of military action in the country. Despite charges that the president is taking too long to decide whether to grant Gen. Stanley McChrystal's request for 40,000 more troops, Kerry said the president is moving at the right pace. 

"What I learned in Afghanistan and Pakistan is that the president is absolutely correct to take this time to let events unfold," Kerry said. "I personally don't believe strategy is defined merely by numbers of troops -- strategy is focused on our ability to have Afghans defend themselves." 

In diplomatic fashion, Kerry assured those in Kabul that the United States has no interest in "calling the shots" in Afghanistan. 

Fox News' Eve Zibel contributed to this report.