"The price of any project automatically increases," Tatiana Mitrova, director of the Skolkovo Energy Center told Reuters.
"Gazprom's relationships with partners, subcontractors, and equipment and service providers are very complicated. They will all ask for a risk premium," she added.
"This, however, does not mean that Nord Stream-2 won't be built," said Katja Yafimova of the Oxford Energy Institute.
However, while Gazprom’s major partners in the projects - ENGIE, OMV, Shell, Uniper, and Wintershall – are likely to accept the risks, smaller contractors will be more cautious.
"Not all partners can afford to see things through with Gazprom," said Valery Nesterov, an analyst at Moscow-based Sberbank CIB.
It is still unclear whether the US President will enforce the restrictive measures. While Trump signed off on the new sanctions on Monday, he did so reluctantly, calling them "significantly flawed."
"Unless Trump takes a really sharp turn, it is highly unlikely that companies that are supplying pipeline goods are going to be punished in the next year or so,” Richard Nephew, a former US deputy chief of sanctions told Reuters.
At the same time, Gazprom’s long-term projects can be affected.
"A lot of companies are now thinking: 'I've got maybe 12, maybe 18 months in which I can do some stuff but after that maybe I won't',” he added.
The Nord Stream-2 pipeline plans to double the delivery capacity of Russian natural gas to Germany from the current 55 billion cubic meters of gas per year.