A shortage of some popular vehicles is hindering attempts by General Motors to boost European sales, the Financial Times (FT) said.

The paper said that General Motors Europe is considering taking on extra staff at its plant in Azambuja, Portugal, to expand production of the (Corsa-based) Combo van after demand exceeded capacity.

This is despite $US298m being spent on 4,000 redundancies at other European plants in order to cut output in the first three months of the year, the FT said.

There are understood to be shortages of at least two other models, although the company declined to identify them, the FT added.

The FT said that GM Europe is struggling to reverse a sharp fall in market share in the first half of the year and is also trying to stem losses, which reached $767m last year.

Jonathan Browning, vice-president of sales and marketing for GM Europe, confirmed the shortages to the Financial Times but said that most vehicles were available.

"In the first half of the year, if we had had better supplies we probably wouldn't have been so constrained," he told the FT.

GM Europe - which owns Adam Opel, Vauxhall and Saab - is now considering taking on more workers in Portugal to expand output of the Combo, which was introduced last year, the FT said.

"We are looking at some additional hiring," Browning told the FT. "It is often the case as you launch a new model that you can sell far above your capacity."

The FT said that other GM executives are known to be frustrated by the lack of vehicles, adding that GM is relying on van sales to reach its target of ending the year with the same quarterly market share - 9.7% - that it had in the full year last year.

So far this year GM's sales of commercial vehicles are up 62%. The FT said.