Deutsche Telekom is considering amending the terms of a proposed merger of its T-Mobile USA business and local rival MetroPCS Communications ahead of a shareholder vote next week, two people familiar with the situation said on Thursday.

Deutsche Telekom has not yet made a final decision on the new terms, the people said.

Deutsche Telekom was not immediately available for comment, while its financial advisers, Morgan Stanley and Lazard , declined to comment.

MetroPCS agreed the deal in October but Deutsche Telekom is now being forced to find ways to charm MetroPCS shareholders after activist investors holding about 12 percent of MetroPCS stock contested the terms.

They are campaigning for others to help vote down the deal on April 12. Deutsche Telekom needs a simple majority of shareholders for the deal to pass.

Paulson & Co, the biggest MetroPCS shareholder, and P. Schoenfeld Asset Management, another big shareholder, both vowed to oppose the deal because of concerns about the valuation and the amount of debt being assigned to the combined company.

Proxy advisory firms ISS and Glass Lewis also advised MetroPCS shareholders to vote against the deal.

The German telecoms group needs to combine with MetroPCS to close the gap with bigger U.S. rivals and free up resources to invest in its domestic market.

Failure for Deutsche Telekom, which already saw an attempt to sell T-Mobile US to AT&T knocked back by competition regulators, could have big repercussions.

Under the October deal, MetroPCS shareholders would get $4.06 per share in cash plus stock equivalent to 26 percent of the combined company. Deutsche Telekom will own the rest.

The new company will have almost $19 billion in net debt, including a $15 billion loan from Deutsche Telekom, which rebel MetroPCS shareholders say is unfairly priced.

Deutsche Telekom shares were up 2.2 percent at 1359 GMT.

(Reporting by Sophie Sassard in London and Philipp Halstrick in Frankfurt; Additional reporting by Harro Ten Wolde in Frankfurt; Editing by Tom Pfeiffer)