The Swiss solar-powered plane whose record-setting, round-the-world flight was put on hold in July by weather and battery trouble has raised the $20 million it needs to finish the trip, co-founder and pilot Andre Borschberg said on Monday.

Borschberg, at the United Nations' Paris climate summit with co-pilot Bertrand Piccard, said backers that include chemical maker Solvay, Swiss lift maker Schindler, power grid maker ABB and Swatch's Omega brand, made contributions.

Borschberg and Piccard had hoped to finish the 35,000 km (21,748 mile), multileg circumnavigation in 2015, leaving from Abu Dhabi in March.