Hamilton said: "I'm trying to catch him up. He's obviously had incredible success over the last few years so I'm trying my best to battle with him and I hope that we can do that in the race tomorrow whatever the conditions are.
"I just feel grateful for the way the year has turned out and that we can be so competitive and really try to challenge the Red Bulls."
“I just feel grateful for the way the year has turned out and that we can be so competitive and really try to challenge the Red Bulls”
He later said the reference to Vettel's career statistics was "a joke", adding: "I've caught four up on him and I told him I have taken four from him. [But] it's not important. Wins are more important, for sure.
"Of course, when you get to the end of your career and look back it is more relevant, but at the moment I just really feel fortunate to be in a position I'm in and to be able to express myself in the car.
"Plus use my talent to the max and have a car that's really beneath me and a team that's really behind me."
He said his belief that the Red Bull was faster was based on information that Vettel had been 0.6secs a lap quicker than him when the world champion eventually got clear of traffic in the last race in Hungary.
The Red Bulls have also looked quicker and more comfortable around the Spa track this weekend - Hamilton said he and team-mate Nico Rosberg, who qualified fourth, had been struggling to get to grips with the car's behaviour during braking.
"We're going to work as hard as we can to beat both Red Bulls [in the race]," Hamilton said. "It's not impossible; we've just got to get our strategy right."
Watch Hamilton's Belgian GP pole lap
Hamilton giggled in delight over the team radio immediately after taking pole and he said he had not expected to qualify at the front.
"It was obviously a good job by the team," he said. "I was so surprised when I crossed the line.
"When I started the lap, it looked like, on the board… I saw on the [big TV] screen [beside the track] that I was about seventh or eighth and I thought 'Oh my God,' especially as it was raining more.
"I went wide in Turn One and the dash display is usually telling you whether you're up or down and it said I was three seconds down and then five seconds and six seconds, so I didn't understand what was happening in the lap but I just kept pushing.
"I could see I was catching Sebastian [who was directly ahead of him] towards the end, but what a blessing. I feel so fortunate to be up here."
Belgian Grand Prix, day three
Sunday 25 August: Race coverage at 12:10 BST on BBC One & BBC Red Button at 13:00 BST, Radio 5 live, plus live text commentary online. F1 Forum, 15:15 Connected TV. Highlights, 19:00 BBC Three & BBC Red Button
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