Macedonia's president says he will veto a law making Albanian the country's second official language, describing the legislation as unnecessary and unconstitutional.

Macedonian lawmakers approved the bill last week in a parliamentary vote boycotted by the main opposition party.

President Gjorge Ivanov said the law would introduce a "very expensive redundancy" in state institutions, "instead of building a multiethnic society through a spirit of dialogue and coexistence."

Ethnic Albanians make up about a quarter of Macedonia's 2.1 million people, and the new law allows them to use Albanian in communications with all official institutions throughout the country.

According to the Macedonian constitution, the president is obliged to sign the legislation if it's approved by parliament in a second vote.