She was speaking as US President Barrack Obama arrived in Hanover at the weekend for a meeting with Merkel and other EU leaders.
Addressing the transatlantic trade and investment partnership (TTIP), Merkel said, "From a European perspective, let me say this very clearly. It is very helpful in order to allow our economy in Europe to grow. It's important for the German economy; it's important for the whole of the European economy.
"And if I look at the progress that was made with TTIP I think we all ought to have an interest in speeding matters up. And I hope and trust that the US President will continue to support these negotiations. We should do our bit in order to make this a success."
Those who favour TTIP have said that alleviating customs and non-tariff trade barriers such as technical standards and requirements will result in economic growth and new jobs.
Opponents fear the compromises will result in lower standards and have criticised the fact that the negotiations and meetings to solidify the agreement have been kept secret.
A survey by the Bertelsmann Foundation found that both Germans and Americans view TTIP with scepticism. A third of Germans oppose the pact, up from about a quarter in 2014.
Just 15 per cent of Americans now say they support the agreement; two years ago, that number was just over 50 percent. Forty-six per cent of US respondents and 30 per cent of Germans said they did not have enough information to answer the question.
Some observers warn a final deal could still be some way off. Ahead of Obama's German visit, the Greens/EFA group published an open letter on TTIP.
The letter highlights concerns about the negotiations and their implications on regulations and standards, including controversial investor protection provisions.
German deputy Ska Keller, trade spokesperson for the group, said, "There is a host of legitimate reasons why citizens on both sides of the Atlantic are opposed to the controversial TTIP agreement: extra-judicial tribunals, which undermine democracy; 'regulatory cooperation', which aims to scale back standards and rules, with negative implications for the consumers."
She added, "Instead of tailoring an agreement to the interests of multinationals, Obama and EU leaders should be focusing on ensuring globalisation is a fair and just development. In our letter, we are calling for a strong and progressive transatlantic alliance, which is possible without TTIP."
In her speech at the weekend, Merkel also addressed the crisis in Ukraine and the Minsk agreement which was brokered in a bid to resolve the dispute.
On this, she said, "We attach the greatest possible importance to the Minsk agreement being implemented as quickly as possible. We will put a lot of effort into making this possible in our talks with Ukraine, but also in our talks with Russia.
"Unfortunately, we still don't have a stable cease-fire. We need to bring the political process forward. And the next few steps we've also discussed very thoroughly."